I'm 38. I stopped caring about what age I was at 30.
As a total random note - I was looking up the first fish I got and returned to my LFS because of aggression. A rainbow shark. There's absolutely no way that fish should've been sold with my 60cm x 30cm tank! Seriously fish says 120x45! The guy said he was surprised the fish was so aggressive to my other fish (at the time 1 Molly, 1 platy, 2 angel fish).