What could it be?

Stuart

Something is growing on the stone with clavularia and is gradually spreading. Should this be dealt with and how? Can it cover the entire stone?

Rodney

If possible, a photo of slightly better quality. As it is, it looks like a sponge, but the little dots are confusing; maybe the clavularia is spreading?

Chelsea567

Yes, the photo is not great; it gives me the same impression as Fyodor's ()—it seems like these are young "shoots" of cavularia...

Angela

I apologize for the quality; I just started getting acquainted with digital SLRs. If you could advise me on the correct aperture, shutter speed, and ISO settings, I'll try to take a better photo. In the meantime, I quickly made another one. I also thought that the clavularia is spreading, but it does pull in the old polyps...

Joyce

100% is growing, you can see the young polyps.

Russell8484

I completely agree, it is growing 100%.

Sara

Thank you for the answers! So over time, can it pull in all the old polyps?

Jason9385

Cavernaria can indeed grow over itself multiple times, significantly increasing its colony. In the photo, there is an example of colony growth in my aquarium - the first shot is from February 5, 2006, and the second shot is from January 20, 2009. It should be noted that I have cut the colony multiple times to reduce its size...