I have a pair of Apistogramma Panduros. They are about two years old. The male is doing great, good color, swimming easily. But the female doesn't seem to be able to get off the bottom. I see no visible signs of trauma, fins look good, no missing scales, etc. She is eating, just can't swim. What could be causing this? I have tested the water, everything looks good. All the other fish are fine as well. Thank you for your help.