Anyone know what kind this is??

[keeka333]

Just curious if anyone knows what kind of urchin this is. I got it as a hitchhiker and it has grown dramatically. It seems to be doing great, and I feed it phytoplankton....it appears as though it eats algea too. I'm mostly just curious about it and I couldn't figure out kind it is.
Thanks for the help!
:happyfish

 

[yellowtail]

edit: whoops,pictures dont show depth.it looked like an indentation in the rock.

 

[keeka333]

hmm, that's the only picture i've got...maybe i'll take another today if he's out and post another.

 

[cathbad]

It's a rock boring urchin. It will eat algae, including coraline, and some macro. I feed mine nori.

 

[ophiura]

Phytoplankton will do nothing for it...it is a grazer and has no means of catching planktonic things. If you don't have other filter feeders in the tanks, save your money. The urchin prefers the big stuff. It does look very much like a rock boring urchin and getting it as a hitch hiker would support this. A clearer picture might not hurt to definitely rule out any thing else.

 

[saltjunkie]

I have 2 pencil urchins that look very similar, but mine are bigger so it is hard to tell. They are cool though aren't they! Do a search on this site for pencil urchins and look at the picture. Maybe you can tell if they are the same. Good luck!

 

[ophiura]

Pencil urchins are what I wanted to eliminate. They are the one uchin NOT considered to be reef safe, so I wanted to double check!

 

[keeka333]

I have researched pencil urchins and the other urchins on this site...and that's why i posted..it didn't look like any of them. It doesn't look like any pencil urchin i've ever seen. I wasn't sure if the phytoplankton would work or not, so i just tried it...someone gave it to me to try. I wondered if it worked cuz it seemed like after i added it to the tank, the urchin would come out (just a coincidence i suppose). I feed some flakes, frozen mysis and frozen brine and the occassional krill to specific fish. I'm assuming these are acceptable seeing as i've had this urchin in the tank for probably at least a year and I would say it's at least quadrulped in size since the first time I saw it.
Thanks for your help!!
(He's not out grazing right now so i can't get a clearer picture of him just yet.)

 

[keeka333]

I did a search on the rock boring urchin you mentioned. I would say almost certain that's what I have. Looks just like some of the pictures that I saw.
Any tips on things I should know about it??
thanks again!

 

[ophiura]

The rock boring urchin is Echinometra and there are no specific care requirements. They will respond to the "smell" of food, but the little stuff they just can't eat. They might take some of the meatier stuff. You can put it between the spines and see if it moves it to its mouth.
The only major concern with most urchins is their ability to bulldoze rocks, corals, etc. So be sure things are well stacked or attached.

 

[keeka333]

thanks for all your help! I appreciate it!
:happyfish