I have a male Greshakie in a 20 gal hospital tank right now cuz he stopped eating and started hanging in the corner by the heater tube.He also had white stringy feces.I think it was bloat , it has now been 5 days in the tank and he is showing signs of recovery.
I am treating him with metrodianizole and salt , temps a little higher (84) and I am currently treating my 75 all male mbuna tank with garlic , focus and metrodianizole crusted food.They all are eating and seem happy and healthy.
Once they stop eating it is much easier to isolate them and treat a smaller tank than trying to treat a large tank with multiple fish.
Hope this helps
