Tuxedo Urchin Died?

[gregony]

I have a 90 gallon reef that's been set up for around 6 months now. It's got three fish - a pygmy angel, maroon clown, and a yellow tang. I have a couple of SPS corals and a couple of LPS corals. Recently my tuxedo urchin that I've had for a couple of years died (I transferred him from my 40) on the glass. Those who know me from my posts know I don't test for nitrites or ammonia, so I don't know what those parameters would be. I do know that everything else in the tank is fine. The corals are doing wonderfully, no snails or slugs died, and the fish are business as usual. I'm going to do a water change to get some fresh salt water in there to soften the blow but other than that, I'm not going to do much else. Last weekend, I did some plumbing work on my refugium/sump, to try to increase water flow through the sump. Doing this, while adjusting the flow, I emptied the outlet chamber of the sump and the return pump blew a lot of air into the main tank. I didn't think much of it at the time, but now that the urchin has been lost, I'm wondering if the zillions of tiny bubbles could have gotten into the urchin and killed him? Or would the pvc cement residue be a more likely culprit. Or could it just an urchin old age kind of thing? Again, nothing else in the tank seems the least bit affected. Any ideas would be welcome.

[Kmoriarty]

If you've had him for a couple years already I imagine that could be the expected life span in captivity. Hopefully the experts will know but if all the other inverts are fine that would be the first thing I'd rule out.

[gregony]

Yeah, I have no idea how old he was. I'm thinking they're supposed to live a long time. I know the long spined urchins can get to be over 10.