Before I went to bed I checked the tank out again, and that snail is still in the same spot for over a hour now still doing the same thing every 16-seconds like clockwork. It has a tube sticking slightly out of its shell, the tube has an opening at the tip and about 15 seconds after the last explosion the opening gets big and then at the 16th second it quickly contracts and shoots a white cloud about 4" straight up into the water column. The flashlight shinning right in his face doesn't seem to phase him a bit. I guess he is pulling an all nighter. I doubt this is bad for the tank water, but I'm not too concerned because I run GAC 24/7 anyway. This goes to show again how much crazy stuff goes on in our tanks at night time. If you don't take a flashlight to your tank at night start doing it. You never know what you may see. Can anybody confirm this is a reproduction thing?