So yesterday I woke up to my black arowana which is about 18" or so with a suction cup in it mouth trying to eat it. I managed to get him to spit it out but, now is having problems with eating. Jaws look fine, fish seems sluggish but, no abnormal breathing. Leading up to this his appetite was normal as well. After removing the suction I did a 50% wc and, add some aquarium salt. Should I be worried. Help plz.