what is this

[tjk971]

I have a little black sac of something growing on a rock in my tank. Its about as round as a pencil eraser. I think it an egg sac but not sure what kind of eggs. Can anyone help.

 

[tjk971]

its the little black dot on the rock

 

[ajnweb]

Hard to tell what it is from the pic, but my guess would be a sponge of some type. I have some blackish sponges in my tank that grow in a pretty much round ball on the rocks.

 

[tjk971]

You think it is. Kinda see through with little dots in it.

 

[DBM Reef]

+1 to sponge i got quite a few black ones

 

[ajnweb]

You think it is. Kinda see through with little dots in it.

More than likely the little dots are holes in the sponge. If you can touch it, it should feel soft like a sponge.

 

[amjc]

My guess is that it is a sponge as well. I have had black sponges in my tank before too.

 

[tjk971]

Thank goodness. I thought it was going to eggs of some sort that I didn't want in there.