What are these small white cotton balls in live rock

[LMDAVE]

I was going to ask about the green hairs also but I think that is caterpillar weed, but what are these white small cotton type balls?

 

[ihavecrabs]

Those are pineapple sponges. They likely hitchhiked in on some liverock or frags. Signs of a healthy system.

As for the algae, unsure. Do you have any that show the full structure of the plant?

 

[LMDAVE]

Thanks, no that is about the most that is on that rock. Way more of the pineapple sponges than the green. This is one of two established live rocks I brought from my LFS when I started my tank a couple of months ago. Tanks seems to be doing fine, just wanted to make sure this wasn't a sign of something bad growing.

 

[ihavecrabs]

No problem.

If that green starts to grow and shows the full structure of the algae, feel free to post it for an ID. Some algae is invasive and incredibly hard to eradicate. Better to catch it early before you have nice colonies growing on those rocks

 

[reefer_2]

Those are pineapple sponges. They likely hitchhiked in on some liverock or frags. Signs of a healthy system.

As for the algae, unsure. Do you have any that show the full structure of the plant?

I have these growing on my frag plugs will it hurt my corals

 

[homer1475]

Pineapple sponges can irritate a coral, but not be able to kill it. The coral should be able to "sting" the sponge and grow into it's space.

 

[Don Zebe]

Those are pineapple sponges. They likely hitchhiked in on some liverock or frags. Signs of a healthy system.

As for the algae, unsure. Do you have any that show the full structure of the plant?

How do I get rid of the pineapple sponges?