I was wondering if anyone could tell me if these are bad or are good for the tank. I have a 20 gallon tank with a rosebud anemone, yellow wrasse, tomato clown, 2 damsels, foxface, crabs, and a horseshoe crab. I have noticed that I have a strange growth coming out of the sand. I thought it was algea but it is not. It is a worm like thing. I have a couple of pictures. Also my live rock has a thick white and pink "mold" growing on it. Is it safe as well? Do I have something wrong with my tank. Sorry, I am still learning everything about saltwater.
I know they are huge, but I wanted to be able to show the detail of the things. I pulled one out of the sand last night. It looks like a worm and all the long things are growing off it it. I have about 6 in the tank and have no idea what they are or where they came from.