sudden urchin death

[shollis2814]

Last night I noticed my tuxedo urchin dropping spines and not moving. I did a quick parameter check. Nitrates 5-10, salinity 1.024, dKh-11, calcium 380, ph 8.1. There is hair algae, caulerpa, bubble algae, and some coralline in my tank as well as some other food sources, so I don't think it was a food issue. I left him be for a bit, but he died.

The only thing I can think of was that I did have a temp swing issue last Sunday. It was caught and rectified, but it did dip into the upper 60s The urchin seemed to recover. Could it have been a delayed stress death from that?

 

[Kershaw]

Could he have been starving to death with you realizing it? How is algae in your tank.

 

[shollis2814]

I had a lot of cyano and coralline. Tufts of hair algae, and some detritus. I feed a mix of omnivorous frozen and phytoplankton a couple of times/week.
My understanding was they also munch on coralline. I have so much of that it is a calcium suck.

 

[Kershaw]

See I have same issue. That's why I have an urchin. But my coraline uses all my alk. Urchins are pretty hardy. I have had my tank hit mid 60s with out loosing Anything.

 

[shollis2814]

Now, I *did* scrape a lot of coralline off the glass, but my rocks are covered. He also spent some time on my clove polys getting some algae off the frag base, but I don't think they would have hurt him.

 

[Tahoe61]

Typically the first suspect is water chemistry, second nutrition. You can feed most Urchins pieces of Nori. They really need a decent amount of coralline.

I used a clip and the urchin went right to the Nori clip every time.