Flagtail power

Fishnerd360

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So I originally thought so too until I read this thread, and also the link within the thread. It suggests that they are a smaller species. But even at 7-8” that might still be a bit big for a 45g no doubt. But they do seem to be good sellers if you were to resale them. Fishnerd360 Fishnerd360

My lfs still has them, they are babys like 1-2 inches long. They seem like cool fish+good algae eaters, tempting to buy, just don't want to deal with trying to sell the fish when too big. Unless there is one 6-7 inches at max, I don't think I could get one until I get a bigger tank.
 
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islandguy11

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Red or yellow tail flagtails will max out at a minimum of 12”-16”+ in the aquaria. Both types will even grow larger in massive tanks or the wild.

Yes, they are great at targeting algae, biofilm, and leftover food/pellets. Hands down the best vacuum fish available in our hobby. Only downside is when larger. Many will go after the slimecoat of bottom dwellers.
So I originally thought so too until I read this thread, and also the link within the thread. It suggests that they are a smaller species. But even at 7-8” that might still be a bit big for a 45g no doubt. But they do seem to be good sellers if you were to resale them. Fishnerd360 Fishnerd360

As per my post above, I just put up a video in another thread: https://www.monsterfishkeepers.com/forums/threads/super-sized-flagtail-snacking-on-gar-slime-video.719653/#post-8124990.

Again I'm not saying there aren't smaller variations out there, both Matteus Matteus and thebiggerthebetter thebiggerthebetter seem to have some very slow growing FT -- but after seeing this huge yellow fin at one of my LFS imo the color isn't really a true size determinant. While I don't know their ages, the yellow fin is about an inch bigger than the red fin. They're both nearly as big as the Pbass:

1379878
 

Vancouver_98683

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There are no members from the Semiprochilodus family that are small in the wild. The SL (standard length) and TL (total length) are listed in the chart below.

TaenIurus and Insgnius are the two flagtail species that are available in our hobby. Include the tail length (TL) to the smallest specie. You’ll see that listed max sizes about 14” +\-. Even if stunted. It will still reach 12” in a 40 gallon.

A quick google browse for flagtail or semiprochilodus for Brazil markets. You’ll see photos of chunky yellow flagtails. Believe those max sizes listed below are modest. I’ve had the red flagtails grow up to 14-15” TL in 2.5-3 years. There’s some in public aquariums that look like they’re 19-20”+

*every 10 cm = 3.93 inches

B4882E01-5EB4-4606-A8DE-67F391B201ED.jpeg5D48FD4B-F433-4531-ACC3-D31A27C1E522.jpeg39CFB7A7-6775-4BF0-9924-8F09019EC4E7.jpeg
 

Matteus

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There are no members from the Semiprochilodus family that are small in the wild. The SL (standard length) and TL (total length) are listed in the chart below.

TaenIurus and Insgnius are the two flagtail species that are available in our hobby. Include the tail length (TL) to the smallest specie. You’ll see that listed max sizes about 14” +\-. Even if stunted. It will still reach 12” in a 40 gallon.

A quick google browse for flagtail or semiprochilodus for Brazil markets. You’ll see photos of chunky yellow flagtails. Believe those max sizes listed below are modest. I’ve had the red flagtails grow up to 14-15” TL in 2.5-3 years. There’s some in public aquariums that look like they’re 19-20”+

*every 10 cm = 3.93 inches

View attachment 1379889View attachment 1379890View attachment 1379891
Interesting. Thank you for posting this. I actually originally thought they grew bigger than these numbers because of some that I have seen in a big pond previously. I didn’t even realize there were many different types either, until the previous post in tbtb thread.

I really wish I knew how to use fishbase. I feel like I need to be able to read, speak, and type German or is that Spanish? I wish there would be a way to identify the different species.

I wonder if perhaps these slower growing specimens are just runts? Maybe that is the explanation?.

Either way, I really like these guys and want to keep learning more about them.
 
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thebiggerthebetter

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Interesting thread. Thanks all. I have learned a good deal. IDK much about the prochilods.

As per my post above, I just put up a video in another thread: https://www.monsterfishkeepers.com/forums/threads/super-sized-flagtail-snacking-on-gar-slime-video.719653/#post-8124990.

Again I'm not saying there aren't smaller variations out there, both Matteus Matteus and thebiggerthebetter thebiggerthebetter seem to have some very slow growing FT -- but after seeing this huge yellow fin at one of my LFS imo the color isn't really a true size determinant. While I don't know their ages, the yellow fin is about an inch bigger than the red fin. They're both nearly as big as the Pbass:

View attachment 1379878
Are we sure these two fish in the photo are the red fin and the yellow fin FTs? My yellow fins had a obviously different body shape and fin shape. These two fish are identical in these terms. I thought yellow and red are indeed based on their natural colors but too are a function of diet. So the real differentiation is in the bio-geometry.

There are no members from the Semiprochilodus family that are small in the wild. The SL (standard length) and TL (total length) are listed in the chart below.

TaenIurus and Insgnius are the two flagtail species that are available in our hobby. Include the tail length (TL) to the smallest specie. You’ll see that listed max sizes about 14” +\-. Even if stunted. It will still reach 12” in a 40 gallon.

A quick google browse for flagtail or semiprochilodus for Brazil markets. You’ll see photos of chunky yellow flagtails. Believe those max sizes listed below are modest. I’ve had the red flagtails grow up to 14-15” TL in 2.5-3 years. There’s some in public aquariums that look like they’re 19-20”+

*every 10 cm = 3.93 inches

View attachment 1379889View attachment 1379890View attachment 1379891
Useful. Thank you.

I really wish I knew how to use fishbase. I feel like I need to be able to read, speak, and type German or is that Spanish? I wish there would be a way to identify the different species.
?? The FishBase primary language is English. There are many sub-sites that are connected to the main mother site and use different languages.
 

Matteus

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Interesting thread. Thanks all. I have learned a good deal. IDK much about the prochilods.



Are we sure these two fish in the photo are the red fin and the yellow fin FTs? My yellow fins had a obviously different body shape and fin shape. These two fish are identical in these terms. I thought yellow and red are indeed based on their natural colors but too are a function of diet. So the real differentiation is in the bio-geometry.



Useful. Thank you.


?? The FishBase primary language is English. There are many sub-sites that are connected to the main mother site and use different languages.
The serious side of what I was commenting about 7997BE31-6203-4BF2-824E-6100744606D4.jpeg
But mostly I don’t seem to understand the science lingo enough to find what I am looking for. So that comment was slightly tongue in cheek.
 
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Fishnerd360

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If I were to say I get one of these guys. Would anyone take it when it gets too big? Not saying I am going to get one, just wondering?
 

Vancouver_98683

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2 different flagtails. Both photos taken when they were 14-15”. Their curiosity for slimecoat didn’t develop until hitting around after 12”.

My suggestion is if u feel that they’re getting to big for the tank, or causing issues. Rehome and get a new smaller one, lol. They’re window cleaning abilities and algae eating and leftover foods disposal is impeccable!!!

D5AD081A-2EE2-45A5-BE33-AD823447D8E0.jpeg

207A20F7-6003-47FD-81A4-CFB8B1E6CC30.jpeg
 
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