i have a 60 gallon tank with a 5 inch oscar, 3 inch red devil, 2 inch carpinitis Texas, 3 inch green terror a jack Dempsey plus about 8 other small fish that aren't aggressive. I plan on buying a 150 gallon tank to move the fish I listed into it they are all pretty small right now and not aggressive towards eachother in wondering when they get larger and there is less of them will the fight? And kill each other?