You should have a supply of Seachem's paraguard and polyguard. When you buy new fish, use the paraguard in your QT tank.....follow the instructions. Both of them are excellent products for killing fish diseases....especially the ones that are hard to identify.
As mentioned before, peas are a great natural laxitive. I feed my guys as a treat a mixture of garlic and peas and freeze it. I give it to them several times a week. Epsom salt is another way of fighting bloat.
No one likes to lose fish, that's why being prepared for problems is one of the keys to healthy fish.
