Some webby thing

It's at the bottom left corner of that rock. It grew to be that size recently. It has been there and tiny tiny (1/8inch) for a real long time now then it grew to this in about a week.

The red tube worm was already there and this doesn't seem to be impeding it... for now.

 

If you mean the fuzzy cocoon thing at base of the rock, looks like a filter feeding sponge to me. I'm no expert but I have a bunch of them in my tank, I'm told they are good filter feeders, nice for the diversity of the tank.

 

I concur with the sponge... I also have them and no probs with them...

 

i 2cond or 3rd the sponge.... I did Some diggin aound here i think i found a match..

Look for :Spirastrella coccinea in the pic color is off but same structure and growth pattern...



Link: http://www.wetwebmedia.com/spongesii.htm


Good Luck..!!

 

Sponge, I had one on my rock too, except it was white.