They are a pain lol! I had some, actually I had alot. I didn't know what they were so I let them grow feeling proud that I had such a thriving colony. Then my bubble got popped when a friend told me what they were. So I tried "picking", "pulling" them off. Ultimately I decided I didnt need that rock as much as I thought I did so I removed it all together, let it dry out completely. After a good scrub and dip it is now tucked away for a rainy day.