filter feeding crab?
 

I just discovered a new nickle sized crab in my tank. The crab was sitting in a high current area with arms that had fans on the them. It was filter feeding with its two front arms in a rapid motion to and from its mouth. The two front arms weren't just hairy, they had specific and multiple fan like hairs/appendages.

Is every crab like this or is this a unique behavior to one species of crab?

- Gary

This is a special type of appendage not found on all crabs. Most likely it is a porcelain crab. Any pics??

Here is one of a porcelain crab. They come in all sorts of colors. Most are white but also pink, blue and black/dark grey.

http://www.astec.ac.uk/staff/goudket...ain%20Crab.jpg

Christy :)

Re: filter feeding crab?
 

I've got some dark blue filter feeder crabs. They're about the only crabs I like in my tanks. Came in as hitchhikers and they're cool :cool:

Does it look like one of these
http://www.canreef.com/phpBB2/viewto...asc&highlight=

I've got 3 (that I know of) in my 90. Hitchhikers that came in my indo rock. :biggrin:

Murray,

Mine are a solid colour.

thanks everyone!

Christy's pic looks pretty much identical to what I can see of the crab. It's very jittery so I haven't gotten a picture yet.

Anyone willing to take a guess at a light brown starfish that completely scours live rock and leaves it white/dead in its wake? Right now the starfish is only half the size of pinky finger nail. Picture comming soon...

Can't believe I'm happy to have crabs.
- Gary

Do a search on 'Asterina' and see if what comes up looks like what you have.

Uh, here is one page I quickly found .. pics not that great but can be used as a jumping-off point for other searches ..
http://www.wetwebmedia.com/asterinafaqs.htm

Quick summary from me though: the jury is out whether they're good or bad. "Good" because they tend to eat undesirable algaes (hair algae, etc.). "Bad" some say because some may nibble at SPS. With that said, I have hundreds of these types of stars, and tonnes of SPS, and never have I noticed any of them being munched by these stars. So I tend to side with the "they're good" camp. But YMMV.

WTH is YMMV :question:

Your Mileage May Vary :biggrin:

YMMV= your mileage may vary :biggrin:

Tony got it right with 'Asterina'. Clearly I'm going to try a little harder to stump everyone.

There was some back and forth on some sites on whether Asterina will eat coraline algae. I watched one in my tank on a couple of different occassions eat everything to the bone on my LR over the course of an afternoon.

Anyone every had a problem with large populations of Asterina that aquired a taste for coraline algae?

Once again...thanks
- Gary

http://www.canreef.com/photopost/dat...rfish.jpg?8747

Asterina picture. You can see a bare white patch in the top right of the picture where the starfish scoured the LR.

- Gary