Help with pond size for alligator gar

[Ryan1783]

hey every one, I recently picked up a alligator gar from a friend and he's about 15 inches or so. I currently have him in a 180 6x2x2. I am think into about getting a intex pool for him. I already know that they have the ablillity of reaching 15' but i usually see them close to 4' in captivity. With the biggest one I've seen being 5'. My question is will a intex pool that is a 12 feet diameter and 33 inches deep be enough for this fish? Thanks every one who can help

 

[MooseTheWizard]

Nope. They should reach their full size in captivity, and if they aren't it is due to a dietary or water quality issue. Assuming the fish will hit 10', you would need a 40'x20' at minimum to keep this fish. For a circular pool you would want a 40-50' diameter.

These fish aren't suitable for captivity unless you are in possession of a phenomenally large pond.

 

[Ryan1783]

Nope. They should reach their full size in captivity, and if they aren't it is due to a dietary or water quality issue. Assuming the fish will hit 10', you would need a 40'x20' at minimum to keep this fish. For a circular pool you would want a 40-50' diameter.

These fish aren't suitable for captivity unless you are in possession of a phenomenally large pond.

Thank you very much for your response, I have decided to will keep him in this pond until he gets larger cuz he is only 15 inches right know, then when we move, I will be getting a big pond

 

[Drstrangelove]

I already know that they have the ability of reaching 15' but i usually see them close to 4' in captivity.

The reason most fish come no where near their proper size is due to people not providing the proper conditions. Fish who are provided the proper conditions ---in captivity--- can and do reach well over 80%, and sometimes over 100% of their size in nature.

This fish is obviously enormously demanding.

 

[Ryan1783]

The reason most fish come no where near their proper size is due to people not providing the proper conditions. Fish who are provided the proper conditions ---in captivity--- can and do reach well over 80%, and sometimes over 100% of their size in nature.

This fish is obviously enormously demanding.

Yeah, these fish will get massive, I already got the pond set up, just need the filters for it

 

[pharmaecopia]

Nope. They should reach their full size in captivity, and if they aren't it is due to a dietary or water quality issue. Assuming the fish will hit 10', you would need a 40'x20' at minimum to keep this fish. For a circular pool you would want a 40-50' diameter.

These fish aren't suitable for captivity unless you are in possession of a phenomenally large pond.

I feel I need to correct a few points here. First there has never been a documented case of an Alligator Gar 10' long. The longest ever caught and documented was in 1991 by Kirk Kirkland. It was 9' 6" is generally considered to be an outlier for the species. Most record weight fish have been in the 8' range.

Here is a little further reading on that. http://www.carpandcatbussters.com/stars/kirk-kirkland.htm


I feel the growth rate of this fish is being ignored. These fish growth very rapidly for the first couple year, but then slows down quite drastically.

Here is an age vs. length chart for alligator gars. I was unable to find the initial paper but found a link discussing it. One key quote from the study:

"Length at age is highly variable for Alligator Gar in the middle Trinity River population between DFW and Lake Livingston (Figure 1). The dashed line below is the average size at age for 119 Alligator Gar from the middle Trinity. To highlight the variability, a 20-year old fish can range from 4 to 7 feet. By the same token, Gar over 7’ have ranged from 19 to 52 years old with an average age of around 34 years. Growth in this river reach is similar to growth elsewhere in Texas and across the species range."

Link
http://discussions.texasbowhunter.com/showthread.php?t=527246

The reason most fish come no where near their proper size is due to people not providing the proper conditions. Fish who are provided the proper conditions ---in captivity--- can and do reach well over 80%, and sometimes over 100% of their size in nature.

This fish is obviously enormously demanding.

The majority of fish that grow beyond wild sizes are usually limited to smaller fish. One of the better examples of this is mbuna cichlids, which regularly exceed wild sizes. This is largely attributed to their diet in captivity.

For the majority of species though average wild adult sizes would be a better comparison for captive fish, not maximum sizes.



To the op, the largest captive raised Alligator gar that I have personally seen is sitting around 5' in length. This fish is in its teens and has been raised in tanks many thousands of gallons larger that what most of even the best of keepers have access to.

Just watch the growth of your fish and upgrade when it becomes appropriate.

 

[Drstrangelove]

Great post. Like the information on the gar. Nothing beats a well made graph.

The majority of fish that grow beyond wild sizes are usually limited to smaller fish. One of the better examples of this is mbuna cichlids, which regularly exceed wild sizes. This is largely attributed to their diet in captivity.

For the majority of species though average wild adult sizes would be a better comparison for captive fish, not maximum sizes.

Official Record Documented with Photographs (from IGFA and Fishing World Records.Com)

RTC (Phractocephalus hemioliopterus) – 63 inches
Clown Knifefish (Chitala chitala) – 50 inches
Arapaima (Arapaima gigas) – 102 inches
Silver Arawana (Osteoglossum bicirrhosum) – 47 inches
Giraffe Catfish (Auchenoglanis occidentalis) – 35 inches
Channel Catfish (Ictalurus punctatus) – 47 inches
Niger Catfish (Oxydoras niger) – 41 inches
Pacu (Colossoma macropomum) – 45 inches
Yellow Fin Pacu (Piaractus mesopotamicus)– 33 inches
Fire Eel (Mastacembelus erythrotaenia) – 30 inches

Total 493 inches



Maximum Sizes Reported on MFK forums for Fish in Captivity

RTC (Phractocephalus hemioliopterus) – 40 inches
Clown Knifefish (Chitala chitala) – 36 inches
Arapaima (Arapaima gigas) – 84 inches
Silver Arawana (Osteoglossum bicirrhosum) – 48 inches
Giraffe Catfish (Auchenoglanis occidentalis) – 37 inches
Channel Catfish (Ictalurus punctatus) – 24 inches
Niger Catfish (Oxydoras niger) – 42 inches
Pacu (Colossoma macropomum) – 40 inches
Yellow Fin Pacu (Piaractus mesopotamicus) – 27 inches
Fire Eel (Mastacembelus erythrotaenia) – 39 inches

Total 417 inches



Total maximum sizes reported on MFK for fish in captivity represents 85% of the total maximum size from official documented record lengths.

These fish I chose because each at one point or another was on my list to raise. (Except the Channel and Pima.) I dropped others because they were much smaller (e.g., Uaru) or much less commonly kept (e.g., lithodoras dorsalis.)

IMO, these demonstrates that using maximum records (documented, not undocumented) x 80 % is a good rough estimate of captivity potential.

I believe I have somewhere seen people claim to have larger RTCs and Channels than this, but I couldn't find the higher numbers.