I currently have a 6" oscar in a 75g tank. Im setting up a 150g tank. It will not be ready for awhile.. but.. can I introduce some new fish to my oscar? Do I have to grow them separately?

Also.. would it be a good idea to mix South American and African chilids?

Approximately what size are the fish you plan on introducing at the time that you will obtain them?

Also, is your Oscar particularily agressive compared to other Os?

On a side note, if you are going to add any fish with the O in the larger tank, I would suggest putting the other fish in before the Oscar and maybe let them create a pecking order first because from what I've seen, it's harder for a fish introduced after a pecking order is established to become a kind of "terrorizer" or "king" of the tank which may or may not keep the O from killing the smaller/younger fish.

The new fish will be relatively young, so they would be small... 2-3" I would guess. Its hard to find older fish here. We dont have too many places to choose from.

My current Oscar is not too aggressive. He is the only Oscar, now, in the tank. His only friend is a random 3" catfish. I do not see them fight. Actually, the bottom feeder (catfish) snuggles up under the oscar at times and seems to lay with him/her.

personally i would not mix south american and african cichlids together. africans generally require different water condition than o's and some can be extremely aggresive.

as for tankmates for an oscar if they dont fit in the oscars mouth they'll probably leave them alone. i recently added two juvenile oscar(3") in with my older ones(10"-11")and have had no probs as of yet.

Add the new fish to the new tank about a week or 2 before adding the big boy. Make sure the new fish wont fit in the big oscar mouth or he will try to eat them. If you are not sure leave adding the big oscar until the babies have grown. They grow quick especially as they are in a big tank so you can feed them well