sponge/worm/?? coming out of rock and upsetting Acan

Question

Sponges??   What is this and is it harmful to the tank? There are several of them (mainly coming out of the same rock) and the Acans that are on the same rock are not getting along well with them. They are attached somewhere inside the rock. Please help! And how can I safely remove them without possibly harming anything else in the tank?

Answer
Hi Tracy:

It looks like a species of sponge, which are harmless. It should not cause any harm to your Acan Coral.  

I wish you the best of luck with all of your future saltwater aquarium endeavors.

Regards,
David

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OCReef.com - Director