i have had my 2 oscars for about 5 months and they are growing lovely i have never kept oscars before so i have been reading up alot about them, what bothers me is what age is it when i ll find out what sex thay are cause i really want to keep both of them the tank there in is a good size if i end up with 2 males will i have to get rid of one? what about 2 females? im not looking for a breeding pair i just want to keep both my oscars my husband takes great care of them and it would be hard to choose which one would have to go. if any one has any advice i d love to hear it thankyou

You could in theory sex your Oscars now if you knew how to do it. However, that's not something you will find easy to do without training. So, I'm afraid you've got a very long wait. If you have got a male and female, they may well start reproducing when they become sexually mature. From my experience, this normally doesn't happen until they're at least 16 months old.[could be earlier, but it's never happened with mine] But if you have Oscars of the same-sex, or even a male and a female, they may never start breeding so you may never know what sex they are. It's a waiting game at the end of the day.

so if i have 2 of the same sex what age will they become aggressive with each other, or will they just get along?

becky wrote:


i believe that you can keep two oscars of the same sex but it's depends on the mentality of the fish. i mean, some are more aggressive than others.

Here's how it goes- aggression wise (to quote monsterfishrescue)

Male + Male: NO

Male + Female: MAYBE

Female + Female: YES

Anyways, venting is very difficult and often yields unpromising results. Even if your experience in oscar venting, results are generally only accurate 75% of the time.

basically, if lays eggs its a female. If it fertilizes those eggs it's a male. If its gentle, its likely a female. If it's aggressive, it may be a male.

its just a case of try it and see unfortunately.......as you cant sex them the only way is to try them together to see what goes down.......

thankyou everyone for your replys my oscars seem very gentle so far even when they are being fed i have nt seen any signs of fighting but they are only 5 or 6 months old so i ll have to wait and hope that they stay the best of friends i will put up some pics of them

on the tenth months, they will establish dominance,
or courtship if fortunate enough to have male & female.
they will be gentler if both are females. if two of them
happens to be both male, territorial supremacy will be an
issue until one of them submit to the other or both of them
are totally wreck.