I have a albino oscar that is flashing its gills out then starts shaking almost like its having a seziure the other two in the same tank dont do this but I have one that goes to the top of the one heater with the albino and they just seem to stay there for a few and swim away and if the other oscar in the tank goes over there they push it away but if I walk up to the tank they all come to where I am at and want to me to feed them there is also a jack dempsey and a pelco in the tank that just stay to themselves plus i have a divider in the tank to keep my two jaguar's seperated since they are mating and are very aggresive right now this has been going on for awhile with the albino which is about 3 and the other two are about 6 months old. I do water changes of at least 25% every other week if not every week and I have a fluval 450 and a bio wheel filter on the tank two heaters and two airators

Is the so mentioned Fish breathing heavily at all? How big is your tank? you should definitely be carrying out a water change once a week, at least a third of the water should be changed.

Okay, we do need you to test the water and give us the readings. That would be ammonia, nitrite, nitrates and pH

i hate to be the one to tell you but for a 150 us gallon tank you are grossly overstocked. a breeding pair of jags alone should be housed in a 150 and 3 oscars and a jack(assuming they can live together happily) should have a minimum tank size of 180. as for the filtration considering the load you should look into another 405 or even an fx5 to get the job done.

sorry to give you the bad news but you are going to in for a real rough time maintaning water quality and aggression with your current setup.