I just noticed some things on the glass of both my tanks, and I've never seen these before. Tried to take a pic, but they're too tiny - they're probably 2mm in length at most. They're oval shaped, and clear - in the middle is what looks like a bunch of small grains of sand. At first I thought it was just sand trapped in bubbles that got stuck on the glass, but when I reached in to touch them, they're solid, with a jelly-like consistency, and they're stuck at one end to the glass. Anyone have any idea what these are?