I have an IM15 that I set up about three months ago. The live rock I used came with some small creatures that skittered around the sand at night that looked similar to the pictures and video below. Recently I had a small dinoflagellate outbreak which so far I have managed by adding Neonitro and manual removal. It seems to be under control, I probably should knock on wood. The same time the dinoflagellate appeared the population of these little "bugs" exploded. At night they are all over the rocks. This tank also has a healthy population of copepods I can see on the glass, but these creatures are much larger. I assume they are harmless and the population will likely regulate itself, but I wanted to verify.



