I have my two little Oscars that are quite funny to see swim around and go at each other. Well ......one go after the other is more correct.

Anyhow, 2.5-3" right now.

When do they become "adults" and possibly show their sex?

I would like to know when to start looking. Im quite puzzled to know if i have two males, two ladies or one of each. I do not want to breed them, but i do want to know what i own.

Thanks.

Oscars mature at about one-year-old. They are monomorphic meaning that male and female look the same so sexing is very difficult. You'll probably have to wait more than a year for them to start breeding, working on the assumption that you have a male and female that is. If you have two males, or two females, you may never know what the sexes.

Well, if one starts laying eggs, you know you've got a female, and if one starts dropping sperm on the eggs, you know you've got a male:lol: Otherwise, it's pretty much impossible, sorry.