Black Moor at bottom of tank

No, I wasn't suspecting it just feeling I had to do something quick. I guess I know enough to sense danger here.

No the only symptoms I've noticed are swim bladder issues, poor diet, difficulty/stringy venting, anti-social behaviour and lethargy but now fatigue...as if something is draining the fish.

EDIT: and now what looks like shortness of breath
 
There's a big risk with using the wrong treatments for something we do not know that is affecting your fish. Switching meds will not do your fish any favor at all and some meds are powerful that they can be draining to some fish. If I were you, until you suspect bacterial infection is involved, I would have just done with the praziquantel first before going over heavy duty antibiotics. Praziquantel is a much milder treatment and can eradicate possible flukes that may be present in your fish. Antibiotics can strain your beneficial bacteria colony so watch your water parameters carefully.
 
OK so if I read you rightly, the tri-sulfa will cover the same bases as the praziquantel would (except for flukes) and I could continue with it if I check for ammonia but if the fish is suffering I could do some water changes and rethink the prazi?
 
It's been a few days and the tri-sulfa indicates that it should have worked by now. I still have spots (new ones) on the fish (tail fins), which is still lying on the substrate.

I plan to now try the praziquantel.
 
Some good news. The black moor is active again and eating well. I guess whatever was bothering it has passed. It has gained some weight.

However, it seems to have both flotation and equilibrium issues. For example it will be happily eating from the substrate but slightly beyond vertically. Then it will level out and move, but fall sideways slightly in the process, as if it were groggy.

I have been feeding it a mix of the gel food I made with the acidopholus, as well as some hikari pellets.
 
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