I just got two northern sucker for my tank one was swimming around normal and suddenly went in to a corner tail up and stayed there I removed him with a net and he went belly up but was still alive I don't think this is swim bladder the tank is 20 gallon with good PH and good ammonia nitrate and nitrite levels.
The fish were acclimated but the one that went belly up had a red nose from overcrowding from where I got him.
The fish were acclimated but the one that went belly up had a red nose from overcrowding from where I got him.