I have had a 2 gallon Fluval spec set up with literally nothing but sand in it for almost a month and half now, and recently (a little over a week ago) added fresh lava rock and a few dead coral pieces from Samoa my friend had brought back. I have nothing living in the tank whatsoever. I've been just thinking about what to put in it. Tonight I turned on the light and found these all over the glass of the tank. I'm assuming they came from the rock from Samoa. My reef-buddy took a look at the picture and said it looks like hydroid medusae. Any thoughts? I'm hearing it's bad news, but I'm not sure what to do about them and HOW bad exactly this is. Thanks everyone!


