I had my 7" id shark that I rescued 8 months ago ( the original owner said the fish was already 2 years old) in my 180 but everything has started to outgrow the shark. Last night he was badly beat up by the other fish so I moved him to my 36"by12". My question is, should he stay in the small tank until it's bigger (12") or try to move him back right after it's healed.
