The suggestions and the questions asked 4 years ago are still relevant.
Tank temp should be somewhere in the neighborhood of 78F.
Water parameters should be 0 Ammonia, 0 Nitrites, <40PPM Nitrates (if you don't have a test kit, go buy one and post results).
Make sure you have enough oxygen by running an air stone, water pump or something to break/agitate the water's surface.
What size is the tank?
What other fish do you have?