Fact or Fiction?

ditto
 
Well its not exactly fiction.

If you keep a fish in a tank thats too small you can stunt its growth, causing it to become deformed and eventually killing it.

Definitely not good practice.

But a fact…
 
The fiction is that fish will not "Outgrow their environment"

the fact is as stated by Carpguy, they will not reach their full size in a small environment, because they will be stunted, and this is definately poor husbandry to put it mildly.
 
Thats because it wasn't healthy while it was in the bowl - it was stunted. A fish is not supposed to "grow to the size of it's environment," but some fish, under the right circumstances (ammonia/nitrite/nitrate levels, enough of the growth inhibiting hormone many fish produce in the water) some fish will indeed because extremely stunted. This is not the same as a fish merely adjusting to its situation - it becomes a health issue.

A common pleco in a 10g tank will mostly likely not look around and say "I'm in a 10g tank so I'll only get 3.5." Chances are, pretty soon you'd have a 10" pleco in there.
 
Don't take this the wrong way anyone, but the thread I posted to answer the original poster's question pretty much covers all of these intricacies. It doesn't matter to me if we retread trodden ground, but there are some good answers in that thread if you're looking for more information.
 
I believe different fish produce different levels of growth-inhibiting hormone - and as I said, it depends on the frequency of water changes and other conditions.


As TPIRman said, that link is a pretty good one.
 
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