Little round thingys

Just noticed these fuzzy little round things growing on piece of rock. Can someone tell me what they are??

 

The look like pineapple sponges to me. If so, they are harmless filter feeders. My overflow and sump are full of them.

 

I have them all over my rock. lol. I don't like them. They're everywhere. :/

 

I don't have too many in my DT. Only a few in low light areas. I'm not sure if they don't like the light, or if my CUC picks them off before they can grow in my DT.

However, they are EVERYWHERE in my overflow chamber and my sump. From what I have read other people have had the same situation, and then they are all suddenly gone one day.

 

Well I have had 'em for a few months.. I don't ever see them move..

 

+1 pineapple sponge

 

So..they are just there? Not specifically good or bad?

 

Wait..I don't have what OP is showing. I have the little white, ring-worm looking thing that's all by itself on the rock. Sort of center/right in the pic. I've had it ID'd as "a pod" by many people, but never what kind. Some say I have an amphipod, some say isopod.(Not trying to steal your thread..)

 

The white spiral is a pileolaria... a tiny worm in the feather duster family. They are beneficial filter feeders.

The pineapple sponges are harmless. They filter feed and help to clean excess nutrients out of the water. So, that part is beneficial. However, they also spread really quickly and they aren't particularly attractive.