Brittle Stars

Tonight, after all lights but my actinics turned off, I was looking closely at my tank. After a minute or two I spotted a small white Brittle starfish. A few seconds later I saw another very close to it. I looked in another part of the tank and I saw yet another. Within a few minutes all of my kids were looking and we saw about 5 more. It appears that they are all over the place. They are all very small, no larger than a nickle from foot to foot.