Long Spine Urchin Shedding

Doug B · Apr 28, 2018

Hello all,

I have a black long spine urchin that has been in my tank for a year or so. Recently it began what looks like "shedding". It is not dropping spines, but what is happening is the black appears to be coming off the ends of the spines. The first thing that came to mind is that it is similar to molting. Maybe it's growing?

This is my first urchin, and my first experience seeing this. So I was wondering if anyone has any experience with this animal that might shed light on what's going on?

Thanks

nautical_nathaniel · Apr 28, 2018

It could be coralline algae growing on the spines

#reefsquad, any other thoughts?

Crabs McJones · Apr 28, 2018

Not 100% positive, but I thought I read somewhere that white spines could be a sign of stress. What are your water parameters?

redfishbluefish · Apr 28, 2018

I'm unsure of what is occurring with the spines going white, but I will state that the biggest problem I've seen with folks keeping echinoderms is that they end up starving. Urchins are algae eaters. I'd start by hand feeding this guy at least two times a week. Fold up a quarter sheet of nori and, using tweezers, hand feed the guy. He should take the nori fairly quickly (within a minute or two.)

Paul B · Apr 28, 2018

redfishbluefish said:
I'm unsure of what is occurring with the spines going white, but I will state that the biggest problem I've seen with folks keeping echinoderms is that they end up starving. Urchins are algae eaters. I'd start by hand feeding this guy at least two times a week. Fold up a quarter sheet of nori and, using tweezers, hand feed the guy. He should take the nori fairly quickly (within a minute or two.)

Actually while they do eat algae, they will also eat "meat". I have had this one for many years, I don't even remember when I got him, or her. But about every couple of weeks I give him a nice piece of clam and if he could smile, I am sure he would because he goes as crazy as an urchin can go. It only takes about a minute for him to eat it. I put the clam as close to underneath him as I can and he maneuvers it to his mouth.
There isn't much algae in my tank but urchins seem to live forever.

Doug B · Apr 28, 2018

crabs_mcjones said:
Not 100% positive, but I thought I read somewhere that white spines could be a sign of stress. What are your water parameters?

To be honest, this tank has been running for a long time, everything in it appears healthy, corals are growing, fish acting normal. So, aside from checking that the dosing pumps don't need to be adjusted every week or so, I do not regularly check water parameters any more. The whole thing is on an apex, and things like temp, salinity, ph, remain pretty stable. I imagine it is possible that there is increased nitrate or phosphate in the system. I will do a water change later today and see if that helps.

Doug B · Apr 29, 2018

Okay, it is in fact algae or diatoms or something. I took a pair of soft tipped tongs and drug them down one spine and the substance came off and it is black underneath. Odd that it started now, after all this time in the same tank. But at least it doesn't appear to be health related. I will however take care to see that extra algae is put in the tank for the urchin.