Hi i just bought a motoro stingray 5 days ago and today he was floating upside down on the top of the tank! it looks like he might have been attacked by my other chiclids but they have never been aggressive with my stringray before, perhaps they just saw him floating and started attacking him. His disk is bubbled and i put him back upright and separted the tank and hes just sitting on the bottom of the tank now and moves his tail just back and fourth. he looks to be breathing alright but might be coughing.... please help i dont want my baby to die! The tank temp is 84, ph is 6.2. HE HAS not been eating for 3 days but first day I had him he ate 3 feeder fish and some blood worms.