What is it?

[Krystalklear]

Hi,

Anyone know what is growing on my live rock. It has recently crept up from the base. It has a leathery feel and encrustes the rock. It can be peeled off at certain parts.

Thanks in advance

 

[HumbleFish]

Sounds like star polyps, but looks like coralline algae. Maybe I'm missing something.

 

[mcgyvr]

Sponge maybe? They come in all shapes and sizes..hard to see what you may be referring to in those pics

 

[billdogg]

Sponge maybe? They come in all shapes and sizes..hard to see what you may be referring to in those pics

^^^What mcgyvr said^^^

If it's the brownish looking stuff, it is almost certainly a sponge.

 

[Krystalklear]

At first it looked like gsp; it has the leathery feel and peels like it, but no polys appear. It is stinging everything in its path as it encrusts the rock. I'm thinking it could be a fire coral?

 

[Anemone]

At first it looked like gsp; it has the leathery feel and peels like it, but no polys appear. It is stinging everything in its path as it encrusts the rock. I'm thinking it could be a fire coral?

If it's a coral, it will still have polyps. If no polyps, then the above if probably right - sponge.

Maybe chicken-liver sponge?

Kevin

 

[Sk8r]

I once had a thing that looked like a piece of old pink chewing gum with goosepimples that looked as if it was trying for polyps, but never made it. It spread and covered a fist-sized rock, and then began to expand outward---a leather coral of some sort. WHen it was upset, it would turn purple, and everything in the tank would close up. Never could identify the thing. I did frag it once with a rubber band, which got it to divide off a piece I gave to my lfs, because they were curious. It never did anything but grow and vary between purple and pink. It was a good bellweather for tank happiness, however.