Thanks Hoppy. I've been misinformed all this time! Then again I'm not looking at the fish tank much if this is the situation. To be completely honest I probably wouldn't be doing much of anything with a fish tank.This is a downright irresponsible post, that should receive careful attention by the moderators. It is just plain wrong. Everyone knows that those alien life forms are completely benign until a very young, shapely blonde enters the room. You can be absolutely safe keeping them in the tank if you can prevent any such blondes from visiting you. I, for example, would never have the slightest problem.