white unknown sponge

Oliver Kubrak

New member

I have a very nice and slow growing sponge in my tank. And I would really like to knwo which it is. Some Pictures first:



It seems not to like light but that might be coincidental. I do not feed the tank much and keep this "sponge" now for Years in a Nano Reef (100l)

Best wishes,

Oliver Kubrak


Team RC
That's funny. You have the exact same sponge on Melev's Id page that's labeled unknown sponge. Fathom that! :) I wish I could help.

Oliver Kubrak

New member
My whole tank looks like that. Sooo many different spieces! I think it i because it is a small tank with 100l and no fish exept a Salarius.


Active member
i've had that sponge before, came on a rock with some shrooms, i had a hard time with it but if its growing in yours you are lucky, its a nice addition to the tank, perfectly harmless, very pretty under actinics, since its white...., it looks like there is alot of small aptasia and bubble algae on the piece unfortunatly

Oliver Kubrak

New member

Not really these bubble algae are pretty nice! I have them for a long time now and they do not spread. They grow in bolws and cup shapes. I will post pictures if you like. I am quite happy there are some Apistasia left. I don't want to get my peppermint shrimps bored. The killed about 20 a day in the last weeks. If I look cloeseley, I sometimes find one. (The picture is a few weeks old) I even feed some to them sometimes from another tank.

The sponge seems hard to keep. Whenever something is wrong wit the water, it shrinks and looks like a dried plant. Quite a nice "fire alarm"...



New member
I have what appears to be the same sponge. It grows pretty quickly in my tank. It has been spreading for a while now. It puts out long extensions and attatches to more rock. It seems to love the shade.


New member
Do you happen to have Carribean rock, FL live rock, etc etc. ???

It looks to be White Calcareous Sponge. However, I don't have a scientific name. Let me get a reference book..

Reef Creature by Paul Humann/Ned Deloach, page 60-61, photograph b.

Looks similar to me. Although if your rock is not from the Carribean area, that might be mistaken. It does resemble the sponge in many ways though.