Red encrusting stuff?

[GeoB]

One of my pieces of live rock has some kind of red encrusting growth on it that is growing vey slowly. There are some button polyps and zoos on the same rock and when the stuff is makes its way around the base of these they elongate and don't seem to like it. I can peel away some pieces of it, but some of it won't peel off. It is dark reddish-brown and has a velvety texture to it. The tank has been setup for two years and the stuff has been there for a long time I don't think it is cyano, that's suppose to be slimey, right?

Can anybody tell me what it is and what I should do about it?

[::pete::]

Encrusting sponge???

[GeoB]

No pics. I need to get a digital camera. I did a quick search on encrusting sponges and I am thinking that is probably what it is. Are these bad to have? How do you get rid of them? The button polyps and zoos that it is affecting are volunteer, but I would prefer to have them over the red growth.

Thanks for the help!

[MikeP]

It's 99% either a sponge or an algae. If it's a sponge it should 'give' when you touch it and feel 'spongy'. When you peel it off what does it look like? Can you see small holes in it or is it solid?

[GeoB]

Here is a picture I just found of something that looks like it except it is yellow instead of red. It is from another forum and somebody said they thought it was either an encrusting sponge or a type of wafer coraline. The stuff I peeled off before was smooth and tan colored on the underside. If it had holes, they were really small. I'll take a closer look at it tonight.

[manny]

Does it look anything like this?

[MikeP]

GeoB - that stuff in the first pic is I believe Lobophora? An encrusting calcerous algae. Supposedly not harmful just ugly and hard to get rid of. I have it in a few spots in my tank. Search on Reefcentral for 'brown encrusting algae' I found some good threads there on it.

[Tim Marvin]

I don't know the name of it, but it can grow very rapidly and kill off anything in it's path. You should be able to just peel it off. It seems to just crash on it's own sometimes also....

[GeoB]

I took a closer look at the stuff last night. It’s actually a brownish yellow, but looks red under the actinics. It looks more like the first photo than the second. It doesn’t give to the touch or have any small holes, so I suppose it is an algae. Some parts of it peel off real nice, some of it can’t be scratched off with a fingernail. If it wasn’t trying to encrust the corals, I wouldn’t mind it being there. It has been growing pretty slowly, so it’s not a big nuisance. I’ll just pick at it now and then and try to keep it off the corals and hope it doesn't go into high gear.

Thanks everyone!