I have two electric yellow labs, one is definately a male, the other I assume is a female because I was told that the female has no black on the lower fins. Anyways, the female looks to be breathing pretty hard and has lost some weight. Her and the male were the same size about a week ago. All my water parameters are fine, other than my nitrates being at 10, which I have done a good gravel vac and water change today. Can anyone help suggest what could be wrong?