So about a week ago my boyfriend and I purchased an adult oscar fish to go in an established 90g with a canister filter. We added some extra bottled bacteria just to make sure everything was set. Already living in there was an adult sailfin pleco about 10 or 11". The tank that he was in at the store had large plecos. The oscar was also a bit scratched up from the large sharp decorations they had in there. He seems to be healing. But he doesnt really seem to be eating. We have tried frozen foods, flakes, sinking pellets and floating pellets. We have also tried live foods but hes just not interested. I called the store to see what they were feeding him and got some of that. He seems to maybe have eaten a couple of those pellets but mostly just takes them then spits them out. Now he seems to be splashing at the surface and kind of making rapid movements randomly. Ammonia, nitrates and nitrites are all low and the ph is where it should be. Any ideas on what is going on or how I could get him to eat?