I have had my freshwater community tank set up for a year now. I change the water weekly along with gravel vacuum, and test the water regularly. Recently i have lost a few of my fish. They get bloated abdomens and are very lethargic, then they start to gulp at the surface for air, then they die. I have tested water, conditions are as normal, ph 7. 1 died this morning (a red dwarf gourmi). Non of my other fish are bloated at the moment, but they do seem to be less active than normal. I am worried I will keep loosing them, I am not sure what is wrong as I have been very diligent in checking water condition, doing water changes etc. Any ideas?
