I woke up a few nights ago from a sound sleep at about 2:30 with no idea why. I did the usual listening for a strange noise, checked the kids and then looked in on the tank. (I don't know if it a good sign that I'm checking the kids first, or a bad sign that I'm glad I do) Anyway, first thing I see is that there's some kind of stuff floating in the tank. It looked like a snow globe that had been given a good shake. I grabbed a flashlight and looked closer and the specks started gathering around the light. Each was about 1/8" long and most of them were oriented vertically. There were thousands of them! My chromis kept darting out of the rocks and eating them and a few were going past the overflow, but over the next 30 minutes they all just seemed to disappear. I have not seen any since and there is no evidence they were there. Any ideas what they might have been?
They looked something like this: