Problems again! This time it is one of my platys. My female platy has always been very healthly and active, healthy appetite etc, but the male platy never seems to leave her alone, and she has been pregnant. A couple of days ago, she must have given birth, the male was particularly defensive of her and she spent most of her time hiding. I then noticed the dark mass of fry was gone, and of course since i do not have facilities for breeding fish, I assume the fry have since met there fate with the other tank members. Anyway, she seemed ok, and the tank was due for a partial water change and I did this the same as always, and since then she has just lost her appetite and spends most of her time at the surface. All others are completly fine, active, healthy appetite etc, no sign of any physical illness on her or the other fish. The male platy has given up interest in her, so I know something is up. Any ideas? Could it be she is stresssed from being hassled by the male and the metabolic stress of pregnancy, topped off by a disturbance with the water change? When I change my water I treat it to remove harmful ions etc, and have never had a problem with stress with my methods in the past.