growing based on the tank

[dwarfgourami]

Kathy Jinkings in her book Aquarium Fish has a good quote on the stunting question:

"It is often rumoured that fishes will grow to the size of the tank they are in and then stop. This is absolutely true. The stopping process is also known as death, and the fish will indeed grow no more afterwards."

Not always true, of course (goldfish have been known to live for a long time in bowls), but I do wonder how many of the fish in my first overcrowded tank reached their natural lifespan.

Still (as all parents learn) it is dangerous to spread made-up scare stories as the very people you want to convince are going to stop trusting you in anything. And I do feel very suspicious about the growing organs bit. Certainly don't remember any swelling in my fish. My friend's husband was keeping 5 tinfoil barbs (and 5 corys and a pleco) in a 13 gallon tank; they just kept dying on him, but did not swell, as far as I know.

I prefer to tell my children that the fish will have an unhappy life and might get poorly; this was quite enough to convince my 4-year-old that we cannot keep a bala shark in a 13-gallon tank. Should be enough for adults too.

 

[Jules H-T]

I had a goldfish in a 30 gallon tank with 3 mates for 10 years. Then his cohabitants died and he had the tank to himself for 10 yrs. Then he was moved into a 20 gallon tank on his own where he proceeded to live a further 5 years.

When he died he certainly didn't look like he was straining at the rib cage with massive organs, and I'm relatively sure his life wasn't shortened as a result of either being in a tank to small, or even from moving to a tank 2/3 the size of his old one 15 yrs into his life.

I believe from the evidence I've seen that for goldfish at least, there is a lot of truth in the statement that the fish grows to the size of the tank.