He is in a 9 gallon flex with plants and mts. The water is checked once every other week and is always 0 ammonia, 0 nitrite, and under 10 nitrates. The water is changed every week and he always seems fine.
I checked him a couple days ago and he was fine eating and swimming. Now he's in the corner of the tank at the top but moves every so often. Is there anything else to do besides more water changes?