My mushrooms are taking over my tank. How do I get rid of some of them? They get over 7 inches wide when they expand! I'm noticing that a lot of them have 2 mouths, why do they have 2 mouths? I've tried to scrub them off of the rocks but they just keep coming back.

They are starting to crowd / cover my other corals.

Any ideas on how to get rid of them would be appreciated!

Angie