Well, I prefer not to use the word common. Most large fish are not commonly kept properly, so they will not commonly grow properly.
Here's a link that instead will give you an idea of how they will grow if raised much better than average:
https://www.monsterfishkeepers.com/...-the-minimum-tank-size-for-a-fire-eel.466681/
Here are some quotes;
1) They grow a 1" every month and they need a 300gallon. They can get up to 40"+
2) Usually they grow about 20", in a very large tank they become even bigger. I'd say you want a 6-8 foot long aquarium.
3) I have a 180g tank. My fire eel got too big for it.
4) M. Favrus - 24"
M. Armatus - 40"+
M. Dayii - 24"+ ( ? my guess)
Fire eel - 40"+
5) On an other forum I've seen 38" fire eels that belong to a guy in austria..but your right,normally, in captivity they don't grow bigger than 30" or so.
6) I have seen two fire eels in person at 3 feet long. One is at the Wet Spot Tropical Fish in Portland, OR, and the other is owned by MFK member Shua. Shua's fire eel is in a 6 by 6' tank and is an absolute beast. It's as thick as my calf.
7) We have several members who are keeping M. armatus well above 24".
8) ....How do you explain the numerous people here who have fire eels well over 36"?
I think you can see the other post I made with quotes of how fast they grow by year 1, year 2, and so forth. Those growth rates I collected from this and other web sites.
Of course, a fire eel that isn't properly kept, can in no way grow like that. However, it has the genetic potential to do that, so imo it should be raised to reach it's potential. Just my 2 cents.
Here's a link that instead will give you an idea of how they will grow if raised much better than average:
https://www.monsterfishkeepers.com/...-the-minimum-tank-size-for-a-fire-eel.466681/
Here are some quotes;
1) They grow a 1" every month and they need a 300gallon. They can get up to 40"+
2) Usually they grow about 20", in a very large tank they become even bigger. I'd say you want a 6-8 foot long aquarium.
3) I have a 180g tank. My fire eel got too big for it.
4) M. Favrus - 24"
M. Armatus - 40"+
M. Dayii - 24"+ ( ? my guess)
Fire eel - 40"+
5) On an other forum I've seen 38" fire eels that belong to a guy in austria..but your right,normally, in captivity they don't grow bigger than 30" or so.
6) I have seen two fire eels in person at 3 feet long. One is at the Wet Spot Tropical Fish in Portland, OR, and the other is owned by MFK member Shua. Shua's fire eel is in a 6 by 6' tank and is an absolute beast. It's as thick as my calf.
7) We have several members who are keeping M. armatus well above 24".
8) ....How do you explain the numerous people here who have fire eels well over 36"?
I think you can see the other post I made with quotes of how fast they grow by year 1, year 2, and so forth. Those growth rates I collected from this and other web sites.
Of course, a fire eel that isn't properly kept, can in no way grow like that. However, it has the genetic potential to do that, so imo it should be raised to reach it's potential. Just my 2 cents.