What is this?

[newlyreefd]

It's all over my rocks and all in my sump. I have no idea what it is and it just started to take over. I don't think it's harmful. But there is a lot of it. Anyone know what it is?

 

[Mike J.]

Pineapple sponges; harmless. They will reduce in number as the aquarium ages.

 

[newlyreefd]

Ok. Cool. I wasn't sure. They are everywhere. Didn't think they were harmful. But better safe than sorry. Thanks.

 

[Boboe77]

Ya those are harmless and i personally think they are kinda cool.