There are tons of tiny little gray dots crawling around in my QT tank. Wonder if the clams came with something -- the only other thing I can think of is that the snail I have in that tank have bred, but those babies are brown and round instead of gray and oval. I'm glad I didn't dump 'em into one of the other tanks.

Here's where a microscope would come in handy -- are they snails, worms, something else? Beneficial, harmful, or neutral?

I guess I'll find out.