i know that gold fish can be in a small tank and i know gold fish get huge in big tanks what is it called which allows them to do this and how is it done?
Goldfish do not grow to "fit" the size of their environment. That statement implies that the fish simply stops growing and retains health. The reality is that if a fish has stopped growing before reaching adult size, then the fish has stunted and it's lifespan will be greatly reduced as a result.
Goldfish and other fish will stunt when kept in tanks not large enough and/or when subjected to poor water quality. Growth inhibiting nitrates and hormones stop their growth while their inner organs continue to grow.
Stunting causes the slow and painful death of the fish. It is wrong.
this is false they do not stop growing the just start to slow down a very little bit they will out grow a bowl and no u cant ever put them in a bowl they need more room and filtration fish do not stop growing if they get to big for te tank they just grow slower