Last night I fed my fish (4 mollies & 4 platies) and pulled up a chair and sat there watching as if I was looking at a computer monitor. They were all eating eagerly and flitting around as usual. Suddenly one of the platies just sunk to the bottom and landed on its side. I stood up and watched and there was absolutely no gill movement or any movement at all - it was stone dead! There was no warning or indication of a problem. Everyone else continued happily eating. I just wanted to share this observation, although I doubt it happens very often and is probably highly unusual.