Can anyone tell me what this is?

[Abbyandgreysmom]

It looks like a little black, somewhat fuzzy ball. It just appeared out of nowhere. I haven't added anything new in quite a while so I'm confused..


Thanks in advance!

 

[Crazyhermitcrab]

I know nothing about saltwater fish. That looks like a plant, although I don't think there are salt water plants, so I'd say it's a coral.

 

[Abbyandgreysmom]

The green one is a coral. The black ball on the coral is what I was asking about...


Thanks in advance!
Bonnie