Help I’d.....

[ezell_tonya]

Hello! Anyone know what this is? Whatever it is it’s growing from underneath the rock in the pick. It also seems to be putting a coating on the rock(2nd pic). The 3rd pic is a view of the bottom of the rock.

 

[KrisReef]

that is a sponge.

 

[James M]

I would remove the black sponge as there highly invasive

 

[ezell_tonya]

that is a sponge.

Thanks KrisReef! It it anything to be concerned about?

 

[ezell_tonya]

I would remove the black sponge as there highly invasive

Thanks James M. Not the best pic. That black in the pic is my niger trigger. That’s it’s hiding place anytime I come to the tank except feeding time.

 

[James M]

Thanks James M. Not the best pic. That black in the pic is my niger trigger. That’s it’s hiding place anytime I come to the tank except feeding time.

Looked like a sponge

 

[KrisReef]

Thanks KrisReef! It it anything to be concerned about?

I've had one similar and at times it grew fairly aggressively and threatened to cover up stuff in the tank. I kept it in check, siphoning and short (5-10 mins max) air drying rocks with a Favia coral on the other side to take out the sponge when I thought I should. I've seen other posts with a similar sponge that was growing so fast that other tank owners considered it a pest.

Keep an eye on it. There are a lot of sponges that are beneficial to the reef and I am not a sponge expert to tell you for certain if the one you have will become a problem or not? Those arms look very similar to the fast-growing sponges I have encountered, you will have to decide if yours is a growing problem. They don't tolerate air very well if it is.