Is this an egg sac?

[sbatestn]

I started my FOWLR tank 3 weeks ago with 5 pieces of LR, a dozen hermit crabs and about 5 snails. All is going well, I think. Water tests show that the tank is cycling as it should, so I'm patiently (impatiently) waiting to add fish. (nitrites and alkalinity still a bit too high). Also, I did my first 20% water change yesterday.

So, about 1 week ago, I found 2 of these "egg-sac-looking-things" on what had been the back side of one of the rocks. I turned it around for better placement and discovered these things (see photo). They weren't there when I first added the rocks.

Can anyone tell me what they are?

Thanks.

 

[jkrentz2515]

You might want to add a picture.

 

[sbatestn]

I just did -- sorry to be slow. Just figuring out how to do this. Thanks for the quick response.

 

[Dave413]

Looks like a sponge

http://www.wetwebmedia.com/spongeidfaqs.htm

 

[Tswifty]

Sponge... harmless.

I have a few in my tank also.

 

[SmknReefer]

Hah, I had one of these pop up when I first started and I assumed it was some kind of fungus...so I scraped it off.

Since I have decided to let them stay...lol.

 

[crvz]

I have a number of those in my setup, they're harmless, and usually indicate a healthy system (or so I tell myself, at least).

 

[sbatestn]

Cool! Thanks for the info. Any idea what kind of sponge? I've been doing some research (thanks for the link), but haven't come across much that is specific to this one.

I'm glad it seems to indicate a healthy system. I'm still waiting through the first cycle to start adding fish!

Thanks again.

 

[Dave413]

Try googling "Pineapple" sponge. here is another link with more info
http://reefkeeping.com/issues/2005-07/rs/index.php

 

[JoeMomma]

I have had one of those in my tank for over a year. I always thought it was some sort of tiny low-light coral. It has never increased in size.

Still, none of the picture on the supplied links looke exaclty like the OP's (and mine).