Tankmates for Tiger Oscar??

While your oscar may still be young, it cannot be guaranteed that dwarf cichlids will last with them. Oscars grow quickly and will eventually try to consume any tankmates that will fit in their mouths. Furthermore, rams are sensitive to water conditions so no way would I consider keeping them with fish that produce too much wastes.

I agree completely. I would personally never put any dwarf cichlids with an oscar.
 
If you get fish that are similar in size now and will grow at a similar rate is best. This will prevent some of the fighting in my experience. You can add a Jack Dempsey or another Central Cichlid that may defend itself and big enough to not be eaten. I have a Green Terror, Oscar and Jack Dempsey together and they do fine in my 215g. They need space as they get bigger and they will get big quick if you feed them well.
 
good tankmates for oscars can be drawn from the following list for example: blue acara, chocolate cichlids, severums, large geos (brasiliensis, red hump, etc.), and large acara in general.
 
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