Not really sure what these are, but I'm resetting up a tank and they're floating on the top of the water, don't seem to be alive but just curious as to what they are. Any info on them would be great. Tried to get a good picture of it, but they're small. I put a staple in one picture to show size.
I have noticed these in one tank I had and they were living on some plumbing that was behind an overflow.


I have noticed these in one tank I had and they were living on some plumbing that was behind an overflow.

