Why is my snapper keep swimming tilted?

Question

my other fish in the tank is doing no signs of funny behavaviour,could it because I overstock the tank.I have 15groupers,1 wrasse,1 snapper,lots of small crabs,hermits,mussels,small fishes as feeds just got soft corals,orange sponges plus mangrove seeds as skimmer.what's wrong?

Answer 1

What size is the tank.. Because its only supposed to be 1 fish per gallon..  If it is swimming tilted it lost its air bubble srry to tell ya but it will die in a couple of days if thats the reason there is nothing you can do...

Answer 2

Did you get it from the ocean?

How big is your tank??