Worlds largest freshwater fish

[synodontisjack]

This is a question which always sparks a couple of arguments, but would everyone say what they think the worlds largest freshwater fish is.

[frasertheking]

depends on what you class as size . length ,weight ?
i would say length a gig but for weight i would think the Mekong giant catfish wins
(http://news.nationalgeographic.com/news/2003/11/1118_031118_giantcatfish.html)

[Danyal]

i don't think the mekong wins for weight, aren't there alligator gars that top 600lbs? ive seen a show called hunt for big fish were a guy caught a 400lb piraiba catfish. i don't think a 16' gigas would exactly be light either. and isn't there monsterous sized wels in the russian lake?

[synodontisjack]

There are a couple of things i was wondering about:
1) the wels cat has been found in the black, baltic and aral seas so is strictly not freshwater.
2) although i dont think the mekong cat has ever been sighted in seawater if it is anything like many other members of Pangasiidae it could be migratory.

[scottgeeze]

What about an Aripima, from what I've seen they can get 15 feet long.

[Chaitika]

Or Sturgeon?

The white sturgeon, Acipenser transmontanus, sought by sportsmen on the Columbia and elsewhere along the West Coast, is the largest freshwater fish found in North America, attaining as much as 1,800 pounds and 20 feet in length.

[akskirmish]

Google of course turned this bad boy up-
http://news.nationalgeographic.com/news/2005/06/photogalleries/giantcatfish/

[Zoodiver]

Arapaima gigas has the largest average adult size for a 100% freshwater fish.

[groovitudedude]

Yeah, but what does Zoodiver know about the Gigas?

:D jk of course

[FSM]

I've got a fish book that says one type of sturgeon gets 29 feet long...I don't believe that though. I've never seen any pictures of arapaima larger than 5-6 feet, although I don't doubt that they get much larger than that.

[demjor19]

i don't think the mekong wins for weight, aren't there alligator gars that top 600lbs? ive seen a show called hunt for big fish were a guy caught a 400lb piraiba catfish. i don't think a 16' gigas would exactly be light either. and isn't there monsterous sized wels in the russian lake?

no. i think the largest was about half of that.

[reddragon343]

i think it wld be one of those giant freshwater stingrays which they caught in the mekong or chao phryah river.

[Zoodiver]

Alligator gar and white sturgeon aren't 100% freshwater fish.

[johnptc]

should this fish have scales ???

[artemis1]

What about chinese paddlefish at 22 feet? of course, there is some debate as to if they're really any more left:irked:

Gigas have the potential to be the largest, but with people overfishing them, a record breaking one is likely only possible in an aquarium.

Mekong giants may be migratory, but they do not enter full saltwater to my knowledge.

i think it wld be one of those giant freshwater stingrays which they caught in the mekong or chao phryah river.

Extremely large, but not heavy. Like a paper plate. lol Also overfished to a frightening extent:irked:

[ewurm]

This thread is all MONSTER! I don't care which one is largest, I love them all.

[catfishlover106]

This thread is all MONSTER! I don't care which one is largest, I love them all.

Right Their Wit Chu Brother! Amen! :ROFL: their all great fishes with all such extrodinary sizes and weights...

[Zoodiver]

This thread is all MONSTER! I don't care which one is largest, I love them all.


We aren't talking loaches.... we're talking REAL fish. :popcorn:

[BaTsBR]

the biggest and heavier I know is
pirarucu - arapaima gigas (wich can have 3 meters and about 250-280kg)
pirarara - red tail catfish (huge huge catfish)
these two can be found in some brasilian rivers, and there are others monsters here too.

like ewurm said, they all are monsters

[synodontisjack]

I doubt a red tail cat would win as the heaviest, they may be bulky but would stil never top 8ft

[Onion01]

huso huso aren't pure freshwater, but i've heard that record was 28'
chinese paddlefish also 20'+
arapaima gigas 15'+
piraiba 12'+
alligator gar (supposedly) 10'+

[Hawkfish3.0]

According to the link in Fasertheking's post, this is a FW ray that reaches 1,000 lbs.

http://i172.photobucket.com/albums/w29/spoolin2g97/stingray_normal.jpg

... and this is a really big freakin sturgeon.

http://i172.photobucket.com/albums/w29/spoolin2g97/sturgeon.jpg

[synodontisjack]

a fw ray would have to be huge to top 1000lb as they are not deep bodied and i doubt any river system could support something that big, the sturgeon is migratory

[Hawkfish3.0]

Hey, I'm just reporting what I read on the National Geographic site in his link.

It does seem a bit far fetched though. However, I don't see a problem with a 1000lb fish in some of the world's largest rivers though. I would say that it's entirely possible, even if not for a FW ray specifically.

[Zoodiver]

Well, if we are looking at fish that go back and forth from fresh to salt - we need to count bull sharks. Isolated populations are suck in 100% freshwater for their entire lives. Adult bulls can weigh in close to 1000 lbs.

[Hawkfish3.0]

Well, if we are looking at fish that go back and forth from fresh to salt - we need to count bull sharks. Isolated populations are suck in 100% freshwater for their entire lives. Adult bulls can weigh in close to 1000 lbs.

True, I believe my Dad's cousin caught one in the lower Mississippi when he was younger. That would be a bit of a surprise if you were fishing for cats! :eek:

[hmoobvwj]

Yea since you guys talk about SW fishes too im gonna say a blue whale. :D

[Hawkfish3.0]

Yea since you guys talk about SW fishes too im gonna say a blue whale. :D

Oh man! Why did you have to go and say something like that???

A blue whale is not a fish it is a mammal !

[synodontisjack]

LOl i love it when people say stuff like that

[synodontisjack]

So are we settled on arapaima gigas as the worlds largest non migratory freshwater fish?

[TLkmDN]

So are we settled on arapaima gigas as the worlds largest non migratory freshwater fish?
yeh but wats the criteria??? weight? height? length?
i think it shud be weight therefore freshwater stingray WINS

[synodontisjack]

freshwater stingrays over 1000lbs don't exist! The arapaima wins because they are the longest.

[Zoodiver]

We should say average adult size (weight and length) of fish that are 100% freshwater. We can rule out rare freaks of size that way, as well as fish that migrate into bracksish and salt water.

Which leaves us with the Arapaima gigas.

[TLkmDN]

We should say average adult size (weight and length) of fish that are 100% freshwater. We can rule out rare freaks of size that way, as well as fish that migrate into bracksish and salt water.

Which leaves us with the Arapaima gigas.
hey zoodiver congrats on being a mod...i only just realised....have u found a new place to work?

[nc_nutcase]

Are we completely ruling out all Sturgeon?

I understand some or even most species dwell in brackish water and on rare occasions may venture out to sea for a very short time…

But I grew up in Detroit, well away from any sea water, and I’ve seen some pretty darn huge Sturgeon pulled out of the lakes up there. Also years ago there was a plaque (probably still there) near the river’s edge (Detroit River) at heart Plaza that had a sketch of a massive Sturgeon being pulled out by a team of horses with a caption of this being the place where the largest fish to someone’s standard was caught (I don’t remember all the details, I moved away from Detroit years ago).

I don’t know too much about these massive cold water fish but I would suspect that there are species that top 10’ whose range is far enough inland to consider them freshwater only…

[Zoodiver]

I think that any pure freshwater sturgeon that gets over 12 feet or so also have members of the species in saltwater.

[ChrisGray]

by weight, a catfish for sure but by length a giga

[Opiate]

i'd have to say giga!!

[cichlaguapote]

a fw ray would have to be huge to top 1000lb as they are not deep bodied and i doubt any river system could support something that big, the sturgeon is migratory

I believe that's the mekong stingray.. it is a river large enough to support such a fish.. there is also a giant S.A. ray I believe.. bigger than tiger ray...

But I think pure FW talking biggest length 'pima wins..

[cichlaguapote]

We aren't talking loaches.... we're talking REAL fish. :popcorn:

Ohhh.. friendly burn... :ROFL:

[hmoobvwj]

OMG lol i forgot that blue whale are mammles lol, i ment whale shark. :D

[Lord Barium]

Heavest freshwater fish is the mekong catfish. I think the largest was 660 lbs and 6-8 feet in length. They do regularly pull up giant mekongs, so this fish most likely wasn't a fluke.

[Moontanman]

This is a question which always sparks a couple of arguments, but would everyone say what they think the worlds largest freshwater fish is.

Beluga sturgeon wins hands down for length and weight, if there were still any alive I would say the Chinese paddlefish at 22 plus feet but they are all gone..... shame, they were an incredible piscavore.....

[synodontisjack]

i agree the beluga sturgeon would win if it were not migratory, but as far as the mekong cat is concerned they are criticaly endangered and are very rarely caught let alone large ones, however there are other members of the Pangasiidae family which grow very large and could be mistaken for the mekong cat.

[artemis1]

Beluga sturgeon wins hands down for length and weight, if there were still any alive I would say the Chinese paddlefish at 22 plus feet but they are all gone..... shame, they were an incredible piscavore.....

Beluga sturgeon are both fresh and salt.

[Moontanman]

Beluga sturgeon are both fresh and salt.

thank you for pointing that out, when I posted I didn't know that was disqualification. How aobut the chinese paddle fish? 22 feet plus, piscavore, sounds about right, might even be one or two left but not enough to make any reall difference.

[yohan]

try guppies haha! ive heard arapima growing up to 16 ft but if chinese paddle fish grows up to 22 ft that has got to be IT!

i did some research about sturgeons and it was said that they mature on sea water meaning most of their life are spent their? or maybe im wrong hehe! their like salmons

[Zoodiver]

Most large sturgeon go into salt water. Smaller species will remain in full fresh (depending on location).

[fishbreeder12]

hmmm gig's for length and meong catfish for weight


(I'd say white stugen for lengeth but the salt water )

[Blue Butcher]

I say Sturgeon. I went fishing in Northern Ontario. We saw one that was bigger than our 12' boat. We pulled our lines in real quick. If caught it would have been our motor and pulled us for a wild ride.

[synodontisjack]

Yeah but were looking for the worlds largest FRESHWATER fish all the larger species are migratory (move from fresh and salt/brackish water)

[lincolngoh]

yeh but wats the criteria??? weight? height? length?
i think it shud be weight therefore freshwater stingray WINS

Maybe should measure by length and breath or surface area:D

... Stingray should win.

[synodontisjack]

How about we find the average of height and length so if the stingray gets 1000lb and is 9ft length it would be 4500 and arapaima 700lb and 18ft so it wold be 6300

[Fish on Fire]

Or Sturgeon?

The white sturgeon, Acipenser transmontanus, sought by sportsmen on the Columbia and elsewhere along the West Coast, is the largest freshwater fish found in North America, attaining as much as 1,800 pounds and 20 feet in length.Thought they aren't 100% fresh water?

[MarbleGoby]

catfish and gigas

[synodontisjack]

Is the worlds largest freshwater fish thread dead or not, everyone put their final decisions as to what they think

[snakeheader]

I think its some kind of catfish or the giga

[flemming]

in de 19and 20ste century many big fish where caugth and killed,the population big fish is nearly gone,but if we give some fish the chance they wil become very huge.
european catfish(15feet)
sturgeon(15/19feet)
airpaima(20feet)
mekong catfish(15feet)
alligator gar(14feet)
we just need to give the fish the chance and the habitat to grow to hug sizes

[Dynamite]

http://www.xyac.edu.cn/jingpinke/yuleixue/yinggu/yg61.jpg
i dont know what species this is but its really big looking. :D

[Spankbelly]

I've got a fish book that says one type of sturgeon gets 29 feet long...I don't believe that though. I've never seen any pictures of arapaima larger than 5-6 feet, although I don't doubt that they get much larger than that.



I think the book means they used to get that big. And still could. But it takes them so long (100+ years) we kill them long before.
I don't see giant trees anymore either. But that's only because we keep cutting down the juveniles.

[Zoodiver]

An arapaima will be 14'-15' in 10 years if given the right home. I've seen 14/15 footers in person.

[holms]

An arapaima will be 14'-15' in 10 years if given the right home. I've seen 14/15 footers in person.

for real ? :eek:


a lot of the so call ' Giant Records ' are just made up and fake .

not counting the Sturgeons ,
largest Fish got to be the Giant Mekong Catfish .
followed by the European Wels and Arapaimas .

its true that the Thai Stingrays might surpass the Mekong Cat ,
but theres too little known about them and no REAL giant records yet .
but the people there are saying that there were a lot of Giant Stingrays netted in the past , might be true .
so who knows .

other smaller giants include the paddlefish ,
Nile Perch and the Alligator Gars .

[1luke1]

If you were fishing in 3-4ft water for pike below a dam, would your choice of lure be a buzzbait, mimick minnow, or jointed rapala???

[Zoodiver]

for real ? :eek:


a lot of the so call ' Giant Records ' are just made up and fake .

not counting the Sturgeons ,
largest Fish got to be the Giant Mekong Catfish .
followed by the European Wels and Arapaimas .

its true that the Thai Stingrays might surpass the Mekong Cat ,
but theres too little known about them and no REAL giant records yet .
but the people there are saying that there were a lot of Giant Stingrays netted in the past , might be true .
so who knows .

other smaller giants include the paddlefish ,
Nile Perch and the Alligator Gars .


Alligator gar don't contend, nor do paddles. They look like they are big when held up by a rope next to a fisherman... but when you've seen those in person as well as a larger fish in person... they don't even come close.

Arapaima gigas are still consistantly the largest by average (weight and length).

I've still never seen a pic of a Thai ray as big as some are claiming. It's all talk until an animal can be found and documented.

[warmouth]

no. i think the largest was about half of that.
Its funny to hear about people talking about alligator gar and alligator snappers who have never seen them in their natural habitat or researched anything besides wiki on them. Ive seen 6ft alligator gar in the boothill in Missouri while fish gigging at night....so I know from many stories from reputable people they can reach larger sizes, afew rare specimens have pictures of 10 ft gar who probably reached over 500lbs here in the mississipi river drainage syster!

[warmouth]

Alligator gar and white sturgeon aren't 100% freshwater fish.
Alligator gar is a freshwater fish that can survive in salt (mainly brackish near a river mouth) water.

[Nabbig2]

Yeah hum...........Well as we know, animals are not to be predicted; they are not like video games, computers, robots, etc.

As far as we know, I would have to say either Arapaima, or Alligator Gar, or Mekong Giant Catfish. I'm not missing anything, right?]

EDIT: *Slaps Self* STURGEON! Excuse me for being too lazy to get my fish book, but I think it's white sturgeon or some other kind. They grow well over 10 feet. So add it to the list.

[Zoodiver]

Alligator gar is a freshwater fish that can survive in salt (mainly brackish near a river mouth) water.

Alligator gar are commonly found living full lives in 100% saltwater. But they are trumped by the size of the Arapaima anway.


It comes down to Mekong cat and Arapaima, it just depends on what one goes with to judge size.... average adult size, or the size of actual largest one caught.

[warmouth]

Everyplace ive seen Alligator gar is neer a river or in freshwater.....where are alligator gar native to SAlt....and how do they spawn their?!. There are stories of 20ft Arapaima....never seen a picture or in person one that big; just like stories of 14ft gar (largest one Ive seen was about 6ft in person and 10ft in a picture) I think you cant go by fish stories. Any fish over 6ft is a giant to me but it could be Arapaima or mekong catfish.....there have been stories in the Ozarks (Cape Area) in Missouri that their used to be 12 ft Flatheads in the Mississipi......but IVe never seen one over 4ft long!

[Zoodiver]

They live very well in the Gulf of Mexico. I've run into many of them while doing shark research down there. I know of several aquariums that display their alligator gar in the full strength saltwater tanks.

[holms]

there have been stories in the Ozarks (Cape Area) in Missouri that their used to be 12 ft Flatheads in the Mississipi......but IVe never seen one over 4ft long!

definitely fake .

[catfishlover106]

wow this is still going on? wow lol :popcorn: want to know whats the final answer

[Bottomfeeder]

If you're looking to compare the largest individual fish of each specis, Meking Giant Catfish. There have been semi-credible reports of huge 20+ft White Sturgeon in a little-known lake in Alaska. I tried to find the wikipedia article but couldn't find it. It is in the "List Of Cryptids" article. I'll keep looking but if anyone else wants to look...I love cryptozoology but I don't wanna go up and down the page all day...

[perchkeeper]

There are a couple of things i was wondering about:
1) the wels cat has been found in the black, baltic and aral seas so is strictly not freshwater.
2) although i dont think the mekong cat has ever been sighted in seawater if it is anything like many other members of Pangasiidae it could be migratory.

You should keep an eye on the fact that other freshwaterfish also live in the baltic and aral sea. Though, there are some parts of these seas that are to salty for the freshwaterfish. A certain part of the Balticsea is known for it's monsterous pike that live there! The freshwater fish probably adapted to the brackish/salty water.

[warmouth]

They live very well in the Gulf of Mexico. I've run into many of them while doing shark research down there. I know of several aquariums that display their alligator gar in the full strength saltwater tanks.
I have heard of them living near the Mississipi river delta and other river deltas leading into the gulf of Mexico but I was stationed farther south in Panama and outside the canal zone Ive never seen a gar while snorkeling in the ocean. Near the river deltas its brackish water, and there are areas where alligator gars could spawn but.....I do not believe they live in the ocean away from river deltas.....but then again I could be wrong.....and there could be man eating flatheads in the Mississippi river and in Table rock lake near the dam! ha ha hee hee ho ho aaah.

[Moontanman]

I have heard of them living near the Mississipi river delta and other river deltas leading into the gulf of Mexico but I was stationed farther south in Panama and outside the canal zone Ive never seen a gar while snorkeling in the ocean. Near the river deltas its brackish water, and there are areas where alligator gars could spawn but.....I do not believe they live in the ocean away from river deltas.....but then again I could be wrong.....and there could be man eating flatheads in the Mississippi river and in Table rock lake near the dam! ha ha hee hee ho ho aaah.

Here in NC we have areas where Gar choose to live all the time in salt water, mostly around docks where fish are cleaned regularly. the are not Alligator Gar but they are gar that are normally found in freshwater. I've even seen them in the near shore ocean around fishing piers but most just inside the barrier islands in the sound. These are wild fish that move from freshwater to take advantage of feeding opportunities. Not sure if this had any bearing on the alligator Gar but these freshwater fish do indeed live freely in full salt water.

[Zoodiver]

I have heard of them living near the Mississipi river delta and other river deltas leading into the gulf of Mexico but I was stationed farther south in Panama and outside the canal zone Ive never seen a gar while snorkeling in the ocean. Near the river deltas its brackish water, and there are areas where alligator gars could spawn but.....I do not believe they live in the ocean away from river deltas.....but then again I could be wrong.....and there could be man eating flatheads in the Mississippi river and in Table rock lake near the dam! ha ha hee hee ho ho aaah.

Agreed you'll see them more frequently right at the river mouth. But I've found them out further and in full strength salt.

[LobstersGoPeenchPeench]

ok sorry i know u guys might think this story is a big bag of b.s. but when my mom was a kid(like 30 years ago) there was a boyscout that went missing one night. i live in cedar rapids iowa. anyways they had a bunch of diving teams looking for the body up and down the cedar river here in town and the divers refused to go down after they searched by the 5 in 1 (5 gate dam that is in the middle of the town in the river) because there were catfish the size of vw bug's. anyways but noone has ever pulled one up... see u think that a actual gaint, on the count that it survived so long, would not hit bait from experience. so just the fact that they havent been pulled up doesnt mean anything. any of u divers feel free to come and search the river but its pretty much impossible to search a whole river like the mekong for giants same with the mississippi river too. they could be hiding anywhere. also we have a roller dam that if anything gets caught in the current its stuck so noone has searched right near it and i wouldnt be surprised if there were massive fish that blow the records out of the water so dont come to conclusions about alligator gars and massive cats in the american river system and along with the mekong such as the elusive 1000 lb ray swimming around on the bottom. plus rays bury themselves in the sand so you would have to use like a small dog for bait if u were fishing for a massive ray.
just my 2 cents

[Moontanman]

ok sorry i know u guys might think this story is a big bag of b.s. but when my mom was a kid(like 30 years ago) there was a boyscout that went missing one night. i live in cedar rapids iowa. anyways they had a bunch of diving teams looking for the body up and down the cedar river here in town and the divers refused to go down after they searched by the 5 in 1 (5 gate dam that is in the middle of the town in the river) because there were catfish the size of vw bug's. anyways but noone has ever pulled one up... see u think that a actual gaint, on the count that it survived so long, would not hit bait from experience. so just the fact that they havent been pulled up doesnt mean anything. any of u divers feel free to come and search the river but its pretty much impossible to search a whole river like the mekong for giants same with the mississippi river too. they could be hiding anywhere. also we have a roller dam that if anything gets caught in the current its stuck so noone has searched right near it and i wouldnt be surprised if there were massive fish that blow the records out of the water so dont come to conclusions about alligator gars and massive cats in the american river system and along with the mekong such as the elusive 1000 lb ray swimming around on the bottom. plus rays bury themselves in the sand so you would have to use like a small dog for bait if u were fishing for a massive ray.
just my 2 cents

I am a scuba diver, I know lots of other scuba divers, I know divers that have swam with very aggressive sharks, some even with great whites (I have my doubts about that), groupers big enough to gulp you down, none of them are afraid of catfish. I also know several divers who actually work on dams, they go down and repair underwater parts often in very deep water. They say they have dived around many of the dams which are supposed to have the giant catfish. According to divers who have actually gone there these claims of giant catfish are indeed urban legends with no basis in fact. they have never seen catfish any bigger than the world record size cats and usually much smaller. Don't think that divers are afraid of fish, they are not, very few fish will attack a diver to start with and the most dangerous are sharks that can take a bite out of you. Even sharks usually leave divers alone if they behave themselves. Those big catfish are just tall tales told by divers who want to see the yokels eyes get big. Yes divers tell tell tales, divers can be BS artists as much as anyopne else, they like to see the looks of WOW on the onlookers when they come up. No giant car sized catfish in dam impoundments or the tale waters.

[plecos_rule5000]

red tail cats get like 900 lbs ..... but id still say gigas

[Zoodiver]

I've never heard of nor seen a 900 lb red tail catfish. Where did that number come from?

[synodontisjack]

wow i didnt know this was still a debate i thought we all agreed on arapaima.

[gigas12]

I think it would be silurus glanis.

[Acheloos]

It is really not easy to answer the question which is the largest freshwater fish, not only because you have to discriminate between pure freshwater fish, migratory fish and fish which come on occasion in freshwater.
A very big (and I mean really big) problem is that most of dates of maximum sizes you can find for the biggest specimens of a species are extremely unprobably and highly likely to be big-fish-stories. To take for example the arapaima, the only reason why so many people believe in this 15feet is because there was one single report from the first half of the 19th century that this fish should grow to this size (ever realized that a 15 feet long fish with only 200kg would look like an eel...). I wrote a longer post about this topic: http://www.monsterfishkeepers.com/forums/showthread.php?t=168521
The same thing is with the wels catfish and many other species too. You will find big-fish-stories everywhere, but if you look how big the actual confirmed records were, you see in general a huge difference.
There are big fish stories for many sturgeons too, as well as for the giant freshwater stingrays and many other ones.
Another problem is how to count, length or weight.

If you only count fish which live in freshwater, there are some very big ones (I don´t write them as a list from the biggest to the smallest):

Wels catfish Silurus glanis: Record size 2,78m and 144kg
Piraiba catfish Brachyplatystoma filamentosum: 2,37 and 142kg
Arapaima : 2,63m and 185kg
Alligator gar: (at least) 2,89m and 165kg
Giant Mekond Catfish: 2,70 and 293kg
Giant freshwater stingray: at leat 3m and well over 100kg
Chinese paddlefish: The often cited report of 7m is only one single report and much larger than anything else, so I would not take it serious. But lengths of more than 3m are confirmed as well a weights of more than 100kg, like the specimen caught some years ago which was 3,30 and weighed 117kg, but actual record sizes would be most probably higher.
There are also some very big other sturgeons which only live in freshwater which are in the 2m range, as well as some other ones.
So if you count only weight, the heaviest freshwater fish with a confirmed weight is most probably the Giant Mekong Catfish, but if you count length there are several species which can reach more length, probably with the chinese paddelfish at the top. This species seems also to be those with the highest average length.
If you count migratory fish you can also count a lot of sturgeons. There are also many figures which are highly dubious like the often cited 8-9m and 1500kg for Beluga sturgeons. Actually the biggest ones which were confirmed were actually about 1500kg in weight (which is really very much over average and as big as a big great white shark), but at this weight they were "only" about as long as 5,5m. A hypothetic 9m beluga would weigh about 6500kg, about as much as a minke whale.
But if you count also species which come only occasional in freshwater, there is possibly even a bigger species.
Sawfish also sometimes swim up in the rivers for example in Australia, and there are many good records of specimens well over 5,5m.

[henward]

easy , search the encyclopedia

[Acheloos]

No, not that easy at all, because you will find a lot of false dates even in encyclopedias. Furthermore many really big species are highly unknown and hardly ever mentioned in normal literature, like the chinese paddlefish, the giant stingrays or the fact that sawfish swim up rivers.

[patrickjohnsgarcia]

woooooooooow i want to keep all those fishes..........

[patrickjohnsgarcia]

i

[patrickjohnsgarcia]

i think its the arapaima!!!!

[invisyblegypsey]

this is cool

[Ramesh]

a fw ray would have to be huge to top 1000lb as they are not deep bodied and i doubt any river system could support something that big, the sturgeon is migratory
Man what do you mean by no river system being big enough to support a 1000lb fish??
Have you seen the Mekong?? I have been there and it's massive and have your heard of the Amazon??
Both these river have the size (Mekong up 4km across, Amozon 11km) and water volume to support such animals easily. The Amazon's volume of discharge alone into the sea can produce fresh water up to 150km out to sea.
River volume and size arise from the area and geographical location of their drainage basins and both these rivers are located in topical areas of high seasonal rainfalls.
Meaning they can easily sustain fish of 1000lb is such species live there....
Knowledge is power man do your research first before jumping to unsubstantiated conclusions.

[Ramesh]

It is really not easy to answer the question which is the largest freshwater fish, not only because you have to discriminate between pure freshwater fish, migratory fish and fish which come on occasion in freshwater.
A very big (and I mean really big) problem is that most of dates of maximum sizes you can find for the biggest specimens of a species are extremely unprobably and highly likely to be big-fish-stories. To take for example the arapaima, the only reason why so many people believe in this 15feet is because there was one single report from the first half of the 19th century that this fish should grow to this size (ever realized that a 15 feet long fish with only 200kg would look like an eel...). I wrote a longer post about this topic: http://www.monsterfishkeepers.com/forums/showthread.php?t=168521
The same thing is with the wels catfish and many other species too. You will find big-fish-stories everywhere, but if you look how big the actual confirmed records were, you see in general a huge difference.
There are big fish stories for many sturgeons too, as well as for the giant freshwater stingrays and many other ones.
Another problem is how to count, length or weight.

If you only count fish which live in freshwater, there are some very big ones (I don´t write them as a list from the biggest to the smallest):

Wels catfish Silurus glanis: Record size 2,78m and 144kg
Piraiba catfish Brachyplatystoma filamentosum: 2,37 and 142kg
Arapaima : 2,63m and 185kg
Alligator gar: (at least) 2,89m and 165kg
Giant Mekond Catfish: 2,70 and 293kg
Giant freshwater stingray: at leat 3m and well over 100kg
Chinese paddlefish: The often cited report of 7m is only one single report and much larger than anything else, so I would not take it serious. But lengths of more than 3m are confirmed as well a weights of more than 100kg, like the specimen caught some years ago which was 3,30 and weighed 117kg, but actual record sizes would be most probably higher.
There are also some very big other sturgeons which only live in freshwater which are in the 2m range, as well as some other ones.
So if you count only weight, the heaviest freshwater fish with a confirmed weight is most probably the Giant Mekong Catfish, but if you count length there are several species which can reach more length, probably with the chinese paddelfish at the top. This species seems also to be those with the highest average length.
If you count migratory fish you can also count a lot of sturgeons. There are also many figures which are highly dubious like the often cited 8-9m and 1500kg for Beluga sturgeons. Actually the biggest ones which were confirmed were actually about 1500kg in weight (which is really very much over average and as big as a big great white shark), but at this weight they were "only" about as long as 5,5m. A hypothetic 9m beluga would weigh about 6500kg, about as much as a minke whale.
But if you count also species which come only occasional in freshwater, there is possibly even a bigger species.
Sawfish also sometimes swim up in the rivers for example in Australia, and there are many good records of specimens well over 5,5m.
I hear you man ...all these sizes often mentioned for pima's and other species are highly questionable. Pima's over 12ft or 4m please show me a pic.
I have seen 3m or 9ft pima's in pics but 14-15ft please if you have seen them prove it. Hearsay and anecdotal evidence means nothing when your talking about fish stories. It's all very much like Chinese whispers without pics as hard evidence.
Everything was bigger in the past that is true but so is the exageration of it over time.

[Acheloos]

What do you mean with "Pima´s"?

[Druu]

What do you mean with "Pima´s"?
Arapaima gigas

[Ramesh]

Arapaima gigas
Exactly.....don't you read the other threads and the abbriviations people use for fish common to MFK. Maybe I should have used gigga's....

[Acheloos]

Okay, all right. Yes, of course you can very often read that the arapaima is the largest freshwater fish of the world. But that´s not the case, its size is highly exagerated. I even started a thread about this issue some time ago: http://www.monsterfishkeepers.com/forums/showthread.php?t=168521
As I wrote on my list the largest actually confirmed arapaima was not even 3m in length, not to speak about the alleged 4-5m. It is only cause of this single mention from the early 19th century by Schomburgk, why you can so often read this absurd sizes.

[Ramesh]

Okay, all right. Yes, of course you can very often read that the arapaima is the largest freshwater fish of the world. But that´s not the case, its size is highly exagerated. I even started a thread about this issue some time ago: http://www.monsterfishkeepers.com/forums/showthread.php?t=168521
As I wrote on my list the largest actually confirmed arapaima was not even 3m in length, not to speak about the alleged 4-5m. It is only cause of this single mention from the early 19th century by Schomburgk, why you can so often read this absurd sizes.
I 100% hear what your saying and I am highly suspicious of such claims but I am very open to any valid comfirmation or evidence of such large fish existing for having had existed. Some members have posted of seeing and even working with fish as large as 14ft of which they should produce some pics

[big E]

I have always been under the impression that the largest pure freshwater fish was Arapaima gigas . The Catfish are the heaviest. I never considered the species that travel between salt and fresh to really count among largest freshwater only fish?

[Acheloos]

If Arapaima gigas would reach 4,5m it would be the largest freshwater fish. But this is not the fact, this species will in excess reach lengths between 2,5m and perhaps 3m. The claims of zoodiver are highly obsure. Why should the arapaimas at his zoo-aquarium should reach more than 5 times the weight of normal arapaimas which are already outsized? A 14 feet arapaima would be the size of a great white shark and be in the range of 1ton.
There are other species which grow longer. For the wels Silurus glanis we have at least one confirmed speciemen of 2,78m, and the giant freshwater stingray and especially the chinese paddlefish can reach total lengths of more than 3m.

[Ramesh]

Zoodiver can fix all this by posting a few pics or by providing us with a link to the place that houses these fish.
I do not doubt his "belief" in the size of the fish I just want to confirm their "actual" size.

[synodontisjack]

If you want evidence of the gigas zoodiver is talking about look in his albums, also the thing i said about the mekong not being able to support a 1000lb stingray was just me getting wound up as i still doubt their existence but yes the mekong could support such a fish if it existed

[Acheloos]

There are some nice photos in his album, but there is still no evidence for arapaimas of the size he claimed. The ones which show the arapaimas next to the people show clearly that they are far away from the alleged size.

[Zoodiver]

Pictures all over the place confirm that arapaima gigas grow much larger than the claimed 2.5M in this thread. Several in my albums are 3 M plus.

Why do I think they grow as large as I claim? Because I've seen them.

I have also seen many self proclaimed "keepers" housing them in terrible conditions more than I have seen them housed correctly. These sub-standard aquariums/pools lead to unhealthy stunted animals. When 80% are kept wrong, suddenly 80% are showing sized that are un-natural. Suddenly, the 'normal' sized fish (3M or more) are becoming the 'freaks' only because keepers are not allowing them to grow correctly.

[synodontisjack]

Pictures all over the place confirm that arapaima gigas grow much larger than the claimed 2.5M in this thread. Several in my albums are 3 M plus.

Why do I think they grow as large as I claim? Because I've seen them.

I have also seen many self proclaimed "keepers" housing them in terrible conditions more than I have seen them housed correctly. These sub-standard aquariums/pools lead to unhealthy stunted animals. When 80% are kept wrong, suddenly 80% are showing sized that are un-natural. Suddenly, the 'normal' sized fish (3M or more) are becoming the 'freaks' only because keepers are not allowing them to grow correctly.

I fully agree, Just look at the amount of them in tiny tanks on youtube. I have seen many threads by zoodiver, arapiamag and others showing huge arapaimas, biggest i have seen in person was 11ft and the aquarium keeping it had to get rid of it due to it growing too large, im not sure where it is now but they had only had it for 4 years when they got rid of it and it was still growing. I have every faith that the arapaima get as big as zoodiver and anyone else who truly knows about these claims.

[synodontisjack]

you really think they will fufill their potential in tanks like these:
http://www.youtube.com/watch?v=cUj5rADPUVo
http://www.youtube.com/watch?v=cUj5rADPUVo
also the pima in the above video is only 2m so think of the tank size.
http://www.youtube.com/watch?v=5v78VmLaukw
http://www.youtube.com/watch?v=RT6Ph_m4pws&feature=related
that one had to be rehomed.................and do you think anyone else has a large enough tank or an aquarium will take it in, i doubt it and it will probably die prematurley no where near its potential size

[Acheloos]

I don´t see any arapaima over 3m at zoodivers album. The only picture which makes a vague size-comparison possible, is this one: http://www.monsterfishkeepers.com/forums/album.php?albumid=558&pictureid=4701
But they are clearly far away from being over 3m. I could imagine that Arapaimas could be able to reach maximum sizes around 3m, but surely not the alleged 4,5m.

[Zoodiver]

Those are young one in that pic from DWA: 6 or 7 feet at most. The ones in Omaha's exhibit are larger than those at this point.

[ctoychik]

Guys,

There is a very large exhibit (rainforest) in Siam Paragon in Bangkok, Thailand. Check out this link http://www.siamoceanworld.co.th/ (click on virtual tour then floor plan). There is info on it in wiki also.

They have a quite impressive size arapaima in there. I have contacted them to get the size of the exhibit and the size of their resident arapaima. In addition to paimas they have a mekong catfish (huge ones too) together with RTCs, pacus and that sort of giants. I am trying to locate the photos of my trip there ...

Check it out on youtube (there is a glimse of rainforest one) - unfortunately ppl tend to focus on sharks and such http://www.youtube.com/watch?v=4TaSSrhMV6k

[abortedsoul]

Wow... I wish I had a large enough tank and wallet to truly care for and breed those crazy huge stingrays out of Thailand... that would be incredible.

[Zoodiver]

Just for a point of discussion, the text from the information sign about arapaima at the Dallas World Aquarium (the largest Amazon basin freshwater display in the world) reads as follows:

"Arapaima gigas can grow up to 14 feet (4.3m) and weigh up to 400 lbs (180kg). Often seen gliding near the surface of the water, this air breathing fish surfaces every 10 to 15 minutes. They are endangered due to over exploitation and habitat destruction."

[Acheloos]

Well, but this doesn´t prove anything. As I wrote in the very first comment in this thread, this widespread dates come from one single hearsay report of the early 19th century. There was never a confirmed report of such a big arapaima, only because this was the very first description of the Arapaima at Europe, all other authors copied the dates. As this dates are absolutley obscure is already clear, because the length-weight-relation is completely out of proportion. The 180kg is probably really around the maximum weight this species can reach, they will become perhaps even a little bit heavier. But not that long.

[Zoodiver]

I figured since they had the world's largest Amazon based aquarium display an a rather large collection of arapaima with a lot of time spent learning about them as a species (at all stages of growth), that they might have the background to justify the information they are putting out there for the general public. Maybe that is just me, though.

[Acheloos]

There are a lot of things which are not true and still very wide-spread. The Aquarium of Berlin also houses some arapaimas and wrote on the homepage that they can reach the nearly always cited 4,5m and 200kg. I wrote to them and told them the background of the dates as well as the actual dates of the largest recorded specimens and the length-weight relations, and they absolutley agreed with me.
This 4,5m and 200 or sometimes 180kg come all from the same original source, and are not based on actual examination. Schomburgk never saw himself a 4,5m arapaima, so I would really not take this too serious, especially given the ridiculous low weight. This is really not a good account for doubtlessness.
To give another example. Yesterday I looked at a book in our local university library about the fishes of the world. The book is really great, but I found again a fatal error. They wrote the wels catfish would COMMONLY REACH LENGTHS OF 3M.
But well, even given the fact that it is written in an academic standard book for ichthyology, this dates are completely false. If 3m would be common, why is the confirmed record only 2,78m? And this was a really exceptional and freakish monster-specimen, which was extremely over the average.
It happens actually comparably often that even scientists use very old and unconfirmed dates woithout any own research.

[perchkeeper]

My guess is on Arapaima Gigas.
Many people say White Sturgeon, but I think it's originally a sw fish that can adapt well to freshwater. Wells catfish don't grow as big as an arapaima. also the wells catfish is prety good to addapt to brackish water but definately not saltwater.

[Acheloos]

As I already wrote, the problem is that the arapaima doesn´t grow as big as you can often read. The giant mekong catfish reaches much larger weights, and at least for the chinese paddlefish there are longer total lengths. So it is neither the longest nor the heaviest freshwater fish.

[Wyomingite]

Hello all. Not many posts here. My monster fish tank is still a few years in the future. Have enjoyed this thread. The largest freshwater fish? Well, here are the authenticated record sizes.

alligator gar (Atractosteus spatula) - 114 inches, 365 pounds in 1991
Asian FW whipray (Himantura chaophraya) - 94 inches dia., 441 pounds in 2007
piraiba (Brachyplatystoma filamentosum) - 93 inches, 313 pounds in 1999
wels (Siluris glanis) - 109 inches, 317 pounds in 2000
Mekong river giant catfish (Pangasianodon gigas) - 106 inches, 645 pounds in 2005
arapaima (Arapaima gigas), pictured below - 98 inches, 330 pounds in the 1990s
After several days of searching, I could find no authenticated record of size in the Chinese paddlefish. However, the preserved specimen in the picture below shows it competes favorably with any of the others, possibly exceeds them.

Here's the source:http://http://www.fishing-worldrecords.com/photo_gallery1.htm

With no authentication, sorry, but 14 foot arapaima, 12 foot piraiba, 12 foot alligator gars and 1000 pound rays are heresay, nothing more. A 14 foot arapaima or 1000 pound ray requires more than a testimonial on a website as proof.;)

I left out all anadromous species since the thread seems to be geared toward completely freshwater species. So, based on factual evidence open to access by all involved parties, the alligator gar is as large or larger than the arapaima and the Mekong river cat far exceeds either in weight. The ray weighs more than any except the Mekong river cat, and the piraiba and wels both rival the arapaima and the gar. Title for largest easily goes to the Mekong River cat. The paddlefish is a wildcard.

Thought I'd throw in my unasked for 2 cents.

WYte

[Wyomingite]

As I already wrote, the problem is that the arapaima doesn´t grow as big as you can often read. The giant mekong catfish reaches much larger weights, and at least for the chinese paddlefish there are longer total lengths. So it is neither the longest nor the heaviest freshwater fish.

Bingo, Acheloos. Many factors can distort perception of just how big a critter is. People will often see what their preconceptions "tell" them they should see, regardless of evidence to the contrary.

WYite

[Acheloos]

Yes Wyomingite, that the thing. Only because there are STORIES about outsized specimens, this doesn´t mean they are true. I have to say that there are some corrections for your list. The largest confirmed wels was even 2,78m and 144kg, but it was not regarded as a fishing record. I contacted the taxidermist which worked on it, and this fish really existed.
To find good background information about the chinese paddlefish is really hard, and I am highly sceptic about the often claimed size up to 7m. My friend Cameron McCormick once wrote about his blog about this issue, I could imagine this could be interesting for you: http://cameronmccormick.blogspot.com/2007/07/megafishes-chinese-paddlefish.html
Here is also a very interesting pdf with a lot of rare photos of the giant paddlefish, including a specimen of 3,3m and 117kg. This is probably the longest actually confirmed freshwater fish of the world, surpassing even the arapaima, the wels and the mekong catfish. Given their extremely low population, there were surely specimens bigger than this one, even if we keep in mind, that they were most probably not the 7m monsters we can sometimes read.

[Wyomingite]

2.78 meters is 109 inches, 144 kg is 317 pounds, both rounded to the nearest unit, LOL. Same fish, I bet, as that website acknowledges records not taken on rod and reel as well, Acheloos.

I'll check out the website on the paddlefish, thanks for the link. I agree it is/was a definite contender. Sadly, I doubt any still live. I've an interest in tales of animals of all types that are huge beyond the norm. 30 foot crocs, 45 foot pythons, etc. IMO, its a psychological phenomena; humans need monsters. In this age of reason and science, with no dragons or Chimaeras, yesterday's written exaggerations are today's myths.

WYite

[lordofthejewsjr]

what about the loch ness monster? jkjk

[Acheloos]

Wyomingite, sorry, I have sometimes really problems to calculate with non-metric systems.
I am also highly interested in outsized animals, no matter if the are giant fish, giant crocs or snakes or for example giant squid. In general it turns out after a closer examination, that the alleged sizes over a distinct limit aren´t true. For example the great white shark. For decades you could read they reach 11m, but those reports were highly questionable (for more info look for example here: http://www.jawshark.com/great_white_recorded_sizes.html ). Or take the whale shark. This often cited lengths of 18 or even 20m are not confirmed records, but only estimated lengths of swimming specimens. Big animals are very often highly overestimated in size. At snakes there is the same phenomen, a lot of allegedly highly outsized freaks, but the actual records are far below them. I wrote some time ago a very long article for a magazine about the alleged monster anacondas. I used a lot of scientific dates of their growth rates and life-spans, as well as the dates of the actual known record specimens and their proportions. To make it short, it is just completely impossible that an anaconda could reach much more than 10m. At crocs there are also a lot of tales of giant freaks. But either there is no physical evidence, or if, it turned always out that the super-giant crocodiles were smaller in life than in the stories of their hunters ( for more look here: http://madrascrocbank.blogspot.com/2008/08/worlds-biggest-crocodiles.html ). At the end, the very largest modern crocs on records were about in the 7m range, what is already monstrous.
Something I really hate is the fact that even many scientists used and still use old unconfirmed dates of alleged records as facts. Just take the arapaima. Why did nearly nobody wonder why there is not a single photographic evidence for one of the alleged 4,5m and how on earth such an animal could weigh only 200kg? There are very much similar cases.

[Wyomingite]

Well, no need to apologize about converting U.S to metric. It confuses me sometimes. I actually do most of my DIY projects using metric 'cuz the math is easier to do in my head.

Sounds like we have a common interest, and have reached the same conclusions. I was a romantic about these things through high school, but a bachelors degree in Zoology toned down the romanticism and forced me to start looking at things from an objective point of view. Thanks for the links. I think I've stumbled onto the crocodile one before, the great white one was new.

......Something I really hate is the fact that even many scientists used and still use old unconfirmed dates of alleged records as facts.

Ditto. The past few years I've started looking at it from the psychological aspect. Humans NEED monsters, even scientists. The wonder of the unknown.

...Just take the arapaima. Why did nearly nobody wonder why there is not a single photographic evidence for one of the alleged 4,5m and how on earth such an animal could weigh only 200kg? There are very much similar cases.

Well, people have wondered, for example yourself and I.

A fish that large would have found it's way into a museum collection or a private trophy room, especially if the genetic potential of the species is such that most individuals should reach that size. In that case, there would have been many fish that size and documentation would be relatively easy to come by; there should be photographic evidence, or even an old mounted specimen, somewhere. (BTW, I agree completely on the alleged weight for a 4.5 meter specimen, its ridiculous).

Nope, if a 4.5 meter arapaima has ever existed, it was a rare example of gigantism and not representative of the average population. Possible? Maybe. Likely? Nope. Claims like that need to be verified, and no authentication exists.

WYite

[Acheloos]

I think one problem is that many people don´t care about biological limits and believe that many animals can grow to every size within a very wider range. But if you look at actual growth rates, possible life-spans and confirmed records of exceptional large specimens (and their numbers in populations) you can exclude some size-claims with nearly 100% certainity. At the case of the arapaima we have the further fact, that the 4,5m comes from a more than 150 years old SECOND-HAND-report. Perhaps this was nothing but a mistranslation. Schumburgk was a german, his guides spoke probably spanish, and how knows what language the people spoke from whom he get this dates? The weight of 200kg could be actually come close to the very largest specimens, and I would predict a possible maximum length somewhere around 3m for this species.
There are limits even for freak specimens. For example at crocs. We have a small handfull of specimens which most probably were about 7m long. That is really monstrous, and nearly 50% longer than what we would already call very big. Given this fact, stories of 10m long crocs are practically not based on facts.

[nishant_datta]

I think one problem is that many people don´t care about biological limits and believe that many animals can grow to every size within a very wider range. But if you look at actual growth rates, possible life-spans and confirmed records of exceptional large specimens (and their numbers in populations) you can exclude some size-claims with nearly 100% certainity. At the case of the arapaima we have the further fact, that the 4,5m comes from a more than 150 years old SECOND-HAND-report. Perhaps this was nothing but a mistranslation. Schumburgk was a german, his guides spoke probably spanish, and how knows what language the people spoke from whom he get this dates? The weight of 200kg could be actually come close to the very largest specimens, and I would predict a possible maximum length somewhere around 3m for this species.

sounds plausible.

Also, recently i saw a documentary on great white sharks in which the camera man (or someone else part of film crew) of JAWS said that when they shot the movie years back 4+ meter sharks were a common sight but now hardly any above that mark are seen and are considered rare. causes attributable were stated to be over fishing and plundering of prey and habitat (pollution perhaps ?). So even if there were 3 m + arapaimas earlier, in our lifetime we may not see one.

[Acheloos]

But exploitation of a species is not everything. In the case of the arapaima, there are still good reasons why we could even today see specimens very near the maximum biological size. At first the arapaima has a huge geographical distribution, and there are still a lot of regions where this species occurs, without any commercial fishery. Furthermore, has been farmed in ponds, without much competition and with a lot of food. It is well possible that the largest ever documented arapaimas will come at the end not from a stream in South-America but from a fishing-or fish-farm-pond somewhere in Asia.
And even if there is overfishing, there are in general still some specimens of extraordinairy size left. For example the beluga sturgeon, which is highly endangered and over-exploited. But there were still in the last decades some specimens in the 4-5m range.
In the case of the wels we have today even larger confirmed (and not just big-fish-tales) specimens than in the past.

[Zoodiver]

In my opinion, the wild is where we will find the largest animals. That competition that captive life lacks is key to bigger, stronger, healthier animals.

[BloodredOscar]

This sounds kinda newbie, but I FORGOT HOW TO MAKE A THEARD! Help?

[Acheloos]

The reason why we find in general most records specimens of a species in the wild is mainly because there are normally much more wild than captive specimens, and the chance that one of exceptional size is found in a zoo or something like this, is just much smaller. Genetics play a big part in the size of most animals, and if only let´s say one in 10.000 soecimens of a population reaches monster-size (let´s say more than 50% more than most other bigger adults), the chance is very low that such a specimen is born and raised in captivity. Furthermore it would not be easy to house most of the bigger species. For a fish of more than 1m, you need a really big aquarium, and that´s very expensive.

[Eoibio]

What about the nile perch?

[Ramesh]

In my opinion, the wild is where we will find the largest animals. That competition that captive life lacks is key to bigger, stronger, healthier animals.

In general the aquatic literature and studies have shown time and time again fish kept in closed reservses or pondages grow larger than fish in streams or rivers. It is the lack of competition and a constant supply of food to predators that allow fish to flourish there.
Arapaima in Asian ponds and other species farmed or stocked in large lakes for sport fisherman are prime examples of this larger size abundence. Streams and rivers seem to allow by the nature of their flow of resouces far less density of large predators along their length than large closed bodies of water.
Aquaria seem to be the opposite for maximum speciems.

[marinebiologist]

Take me seriuos here! I believe in the lockness monster. He is the biggest freshwater fish

[Zoodiver]

In general the aquatic literature and studies have shown time and time again fish kept in closed reservses or pondages grow larger than fish in streams or rivers. It is the lack of competition and a constant supply of food to predators that allow fish to flourish there.
Arapaima in Asian ponds and other species farmed or stocked in large lakes for sport fisherman are prime examples of this larger size abundence. Streams and rivers seem to allow by the nature of their flow of resouces far less density of large predators along their length than large closed bodies of water.
Aquaria seem to be the opposite for maximum speciems.


That's interesting. Usually the generally accepted idea - especially with very large aquatic aniamals - is that they don't grow as big in captivity.
Competition for food means the prime animals survive. The faster/bigger/smarter will be around the longest.

I would never expect a river fish to thrive in a pond. Sure they live and grow up, but it's not a good replication of the natural environment, so we shouldn't assume they will develop the same way in that situation. Also, most captive stock is fairly young compared to the natural life span of these fish in the wild. And fish will continue to grow for their entire life - though we know they do slow that rate once reaching adulthood.

Captive animals seem to be fat for the most part. They are underactive and over fed. This is not a good example of what the fish will do in the wild, so we can't really use animals raised in subprime conditions.

[Ramesh]

No they don't grow large in Captivity becuase I am not talking about aquaria like the facilities you house your fish in. Captivity is a zoo like your fqcilities where fish are feed not like in large ponds and reserves where they find there own food.
I am talking about systems like large oxbows, pond, dams and reserves that hold large amounts of water. There species like Arapaima, Trout, Bass, Barrimundi, various catfishes, Cichlid and Carp and other species prized for food or sport are stocked becuase they do exceptionally well under such conditions.
They are all prime examples of this larger size abundence e.g Bungsamlan Lake in Thailand.
All fresh water fish largely come from streams or rivers so why would you expect them not to do well?
In closed systems all over the world they thrive and because of this fact and they are introduced and stocked because they can grow fast and large under such conditions.
Closed systems like your aquaria are poor simulations of natural conditions under which fish can become trapped becuase it is you who feed them and make the fish fat.
It more natural large closed systems where predators are free to roam and hunt as they naturally would do they grow lager and faster than their relatives that live in streams and rivers. This is what the literature I am talking about supports time and again.
Otherwise why stock lakes and reserves with fish for food and sport if the river fish would not do well there??
If it didn't work and produce large, healthy fish why do they stock lakes and reserves all over the world with various river and stream species??
I agree feeding fish doesn't simulate nature but thats not how you get big, health fish.

[Zoodiver]

I consider "In captivity" to mean in an enclosed and controled area where they are depending on humans to care for them. To me, stocked in a lake is just introduction into another non native area of the wild. Those aren't being raised, they are living on their own - like you said. Most zoos in the US don't tend to raise arapaima in ponds or lakes. They are housed in tanks/displays with closed loop filters. As a result, not all arapaima cared for in captivity have become the over weight and growth stunted animals most see when thinking of large captive species.

[Ramesh]

I knew we were on the same page mate.
I am quite sure that the upper size limit achievable for alot of fish species is seen in these fish that live in such non native wild introductions.
Many stocked species reach near record or hold many of the recognised size and weight records.
This leads me to believe that the 3m plus Arapaima are certainly very rare and the 4-5m specimens simply the stuff of exaggeration.
In Thailand were they have been stocked and grown extremely well in wild like introductions into very large closed systems they have yet to broken 3m.
These fish have beed in these systems long enough (10yrs) to attain such lengths and are not eaten but released to continue their growth.
This again brings us back to the 3m plus Arapaima you have worked with and at what facilities they are at??
Because I am sure they are still there and can be quickly documented for scientific verification.
If they are not 3m it is an honest mistake that I can easily upperstand as I dive and spearfish and have done so all over the world seeing a great many large species of fish and wonderful array of others in the wild.
If they are close or over we could have new record/s for the species which is new information and is why such facilities keep these animals so they can educate and provide us with information about the species we sometimes can't get or observe in the wild.
Just do it zoodiver.

[Zoodiver]

None of the largest arapaima I worked with are living today. There was an ozone injection accident that wiped a lot of the tank out.

[Ramesh]

Did they measure the dead stock and take notes of animals in the tank??
Did they send some of the animals to Universities or Museums for data collection or so they could add them to their speciemen collections??
Some factual information about these animals must exist.
It's such a shame to loose a tank full of monsters and not to have assessed their loses properly.
Didn't they know they had some of the largest speciemens in the world??

[Zoodiver]

Often times places that lose stock like that don't want to talk about the mistake or share details about it. Documenting the dead ones would only draw attention to the accident and create an issue for them from groups like PETA and the like.

As for knowing they had the largest.... the keepers probably are going by the idea that they usually get to that size if kept right, so nobody would have felt the added urge to make note of it.

[Finalfire9]

Or Sturgeon?

The white sturgeon, Acipenser transmontanus, sought by sportsmen on the Columbia and elsewhere along the West Coast, is the largest freshwater fish found in North America, attaining as much as 1,800 pounds and 20 feet in length.

Its the sturgen in america

[the big kahuna]

my vote goes to THE LOCH NESS MONSTER

[peewee]

sturgeons, no doubt.

[uting]

Gigas no doubt! plus do you think Chinese Paddle Fish are still in this world

[dpk2313]

sturgeon
http://www.abovetopsecret.com/forum/staff/gazrok/fish.jpg
http://www.cryptozoology.com/cryptids/images/sturgeon.jpg

[Moontanman]

Gigas no doubt! plus do you think Chinese Paddle Fish are still in this world


It is remotely possible that a few Chinese paddle fish are still swimming around but they have been cut off from much of their former range and completely cut off from their spawning grands. It's doubtful any reproduction is going on so any individuals left are pretty much doomed.

[Acheloos]

There is the big problem with sturgeons because most of them are anadromous and no true freshwater fish, and the Arapaima is still much smaller than most people think. At the end giant Pangasianodon catfish and possibly giant freshwater stingrays are the heaviest and chinese paddlefish and giant freshwater stingrays the longest.

[selki]

most people cant accomodate these species anyway

[uting]

so sad I hope the Chinese Paddle Fish has another habitat in another river.

[perfect_prefect]

http://www.associatedcontent.com/article/1510297/giant_freshwater_stingray_weighs_in.html

does this count for weight? and it was even rod and reel caught and not netted.

[arapaimag]

http://www.associatedcontent.com/article/1510297/giant_freshwater_stingray_weighs_in.html

does this count for weight? and it was even rod and reel caught and not netted.

They guessed on the weight.

Here is a link that explains what happened.

http://www.livescience.com/animals/090310-giant-stingray.html

[perfect_prefect]

damn, that sucks that they didnt weigh it. too bad though it could have been the world record. maybe, maybe not. maybe in a couple years someone will catch it again and weigh it this time.

[arapaimag]

I think that secretly we all want the huge sizes of fish that myths have perpetuated to wow and amaze us and our friends.

But taking the last 2 lines of one of Lucretius's most philosophical passage's "the mask is torn off, the reality remains"

If you read again the National Geographic article link I sent in my last post in this thread, the answer to this thread's question is answered as to what is the largest freshwater fish ever recorded.

This is by reality 646 lbs not by myth 2200 lbs or whatever fiction we might have read.

I never would have believed the low weight having grown up reading and yes believing the nonsense of fish stories of 1600 lb and larger fish and 16 foot wels and arapaimas and 23 foot chinese paddlefish. But in reality thats all they were........fisherman's stories.

Often quoted as being "credible accounts" because they were announced by "scientists". Who in some cases there is no record of or they heard the size second hand from a fisherman. If they actually had measured the fish it would have been accurate sizes like 16 feet 4 and 3/4 inches. Weights would be to the pound at least not rounded off to 2200 lbs.

[arapaimag]

damn, that sucks that they didnt weigh it. too bad though it could have been the world record. maybe, maybe not. maybe in a couple years someone will catch it again and weigh it this time.

The article seems to indicate they did catch it again one month later. Perhaps they were reluctant to try to weigh or measure it because the largest ray ever caught died when they did.

[BigTim15]

well i am probaly going to sound stupid saying this but i think that it is the fw ray..and i think that there are much bigger rays out there

[ljriggz]

One thing everyone seems to forget when they knock gigas is fish have whats called indeterminate growth, they grow all their lives and based off how fast gigas grows, it can be a long lived fish, due to over fishing and people now figuring that their may be more than one species of aripima we may never see the 15 footers, the ones in captivity may not be the same species or locality of the ones that reached 15 feet. but get the water right feed it well and keep it alive long enough you will see 15 footers, just not in home aquariums.

[nishant_datta]

One thing everyone seems to forget when they knock gigas is fish have whats called indeterminate growth, they grow all their lives and based off how fast gigas grows, it can be a long lived fish, due to over fishing and people now figuring that their may be more than one species of aripima we may never see the 15 footers, the ones in captivity may not be the same species or locality of the ones that reached 15 feet. but get the water right feed it well and keep it alive long enough you will see 15 footers, just not in home aquariums.


this makes a lotta sense. kinda like a siberian tiger being double in size to a sumatran one. similar analogies are already there in the fish world as well. Isn't the chinese paddle fish also entirely FW ? Pangasias and CPF may out weigh/grow the paimas.

[Acheloos]

No, you will never see a 15 foot arapaima. What you forget is the simple fact that those myth comes only from one single second-hand report with a completely absurd length-weight-relation. Besides this one single and not-trustworthy report there is no, and I mean really no, indication for arapaimas of this size. And there are still a lot of regions where they are not overfished, and even there sizes of 2,5m are already highly unusual. With optimum conditions you will possibly once see arapaimas in the 3m range, but never much bigger.