When to add an oscar?

[Gruff Master]

15 Convicts? Yeah, I would lose a bunch of those. I'm sure you know by now that it only takes two to quickly turn into two-hundred. I think that by having such a large tank that you have a greater chance of keeping an Oscar with the smaller fish that you mentioned. From the size that you gave of the other fish, they aren't that much smaller than the Oscar that you want to add. In the end the Convicts will be smaller than the Oscar anyway, even if it is introduced once the Convicts are bigger. A 300 gallon should be plenty of room to house an Oscar with dithers and smaller cichlids. Just provide enough places for the smaller tankmates to use as cover. I've seen smaller fish live with much more ravenous fish in much smaller tanks. Just keep an eye on them in case the Oscar ends up being a glutton.

 

[PSU21Reef]

My oscar is the same way. He's about 10" and lives with a few smaller fish including a 3 inch convict. He has never tried to eat any of them. It just depends on the oscar.

not all Oscars will just eat their tank mates,mine actually doesn't eat any of the smaller cichlids at all,its a good thing to be honest,I have a 2 inch convict,3 inch firemouth,3 in half inch texas,3 inch salvini that he can easily eat with no issues.I say mix it up though,don't go with two oscars honestly.Go with a jack dempsey,green terror,salvini,or a texas.