I love my pair. And for the record, 4x2x2 is adequate for a pair. The width really helps. Mine are 7 and 8 inches long and look tiny in there lol. I want to upgrade though. Wouldnt mind a 6x2x2....
i have to totally disagree with this im affraid. have you ever seen a fully grown oscar? if so there is no way you would say that a 4x2x2 is adequate. not even for a single fish at 13 inches+. water volume isnt everything its room to move as well.
my oscar was in a 5x2x2 and i would say that was a bare minimum for him and i would only add another if they were a bonded pair. your fish look small in your tank because they are only small fish. at 7-8 inches they are just over half way to being fully grown if cared for right. yes a 4x2x2 is ideal to grow some juvis on but as soon as they start getting bit they need space. i had the same oscar in a 6.5x2x2 tank before i had to downsize and it was a perfect tank size for him and his tank mates.
op - please dont cram 2 or even 1 oscar in a small tank its not fair. a 5x2x2 tank sounds and looks massive to begin with but they are not when you want to deal in big fish.