I came home today to find this clear, slimy substance hanging off some of my rock. Everything seems fine though, in fact, all my corals look excellent. I have no clue where it came from. I do have a mating pair of oscellaris clowns, but I do not see any eggs and they have not yet spawned in my tank. Maybe they have and I just can't see the eggs? Would a clown pair spawning create this substance in a tank?