Alien eye chalice white in spots since last night??

Okay I think I may know the culprit on this one, but thought I would run it by the experienced folks.

My alien eye was beautiful burgundy with green polyps last night. This morning I woke up to a whole section of it white, like someone had shaved the color right off.

Is it plausible that it is my tuxedo urchin? My short spine urchin has never bothered anything. Short spine hangs in the cave and then on the glass at night. In the last couple of weeks, I have seen thin trails of coraline algae missing from rocks, not that big of a deal since its small amounts, but the alien eye is another story mainly because it is my husband's favorite and since I stay home full-time, its his long hours of work that funds the tank. (Although he tells me its family money.) He is a generous man, but money is not endless so I hope to figure it out.

If it is the tuxedo, I have no idea how to find it. It's about size of quarter and we never see it.

Thanks.

This is one pic of the current crappy condition vs the previous condition in our biocube under poor lighting. The alien eye had gotten deeper burgundy color with really green polyps. Then overnight it was destroyed.
I would think that if the short spine urchin did this we would have seen it previously.

Could the tuxedo do this?

I don't see a pic? I had a tuxedo urchin in my other tank and it was a coralline algae eating machine but never noticed it eating my chalice, monti's or any other type corals. It was more apt to pick up or knock over my smaller corals that weren't glued down.

Hopefully here are the pics. What would have done this? Something has to have been munching on it.

The top pic is what it looks like now and the bottom pic was in the biocube? How long ago did you move it? Where is it positioned in your tank and what lighting is it under now? The reason I ask is it looks more like bleaching to me. Some types of chalice do better under lower/bluer lighting and color up more. Then there are some types that do better under the higher lighting conditions. The alien eye chalice seems to like the lower lighting more.

I wish I had a picture of it in the 90, but it's not my favorite coral although I liked it much better than I do now. Both pics I posted are in the Biocube because until I figure out what is doing this it is safer there.

Okay so we moved it from Biocube (June 2012)
to 40 gallon with T5 HO 78 watts total and high in tank plus 36 watts LEDs (August 2012)
to 90 with LEDs and T5 HO about 2/3 up the 90. (December 2012) We acclimated it over weeks as my husband made out lighting and we did it in 2 phases.

Nothing has changed in the last 2 months, except adding a tuxedo urchin and up by the alien eye chalice is an area that has had the coraline algae removed from the rock. We also have a short spine urchin, but it was in the tank since December 2012. Other tank inhabitants are tiny hermits, snails, 2 urchins, clowns, coral beauty (never has bothered anything), YT, 6 line, 2 scissortail gobies, serpent star, cleaner shrimp and 1 small sally lightfoot crab (only seen it pick off rocks).

I also have a few bristleworms. Could there be another hitchhiker that I don't know of?
Maybe I'll try to figure out how to hook up a web cam and put the alien eye back in tank.
Thanks for the help.

Top pic is now.
Bottom pic is in Biocube.

But it was darker and growing new ridges, expanding in new tank doing very well until 2 nights ago.

Hmmmmmm, I am still leaning toward bleaching but can't rule out the urchin or another pest. Can you move the chalice to a more shaded area and still have moderate flow to it? I would at the very least try it see what happens.

I will try that but it looks like something took sandpaper across it and its flaking. I have had it bleach before. Its 12" away from the light. We'll see.

If you think something is munching on it, I'm going to take a guess its the short-spine. They are reef-safe with caution and my purple short spine was the one who ate my coral. The tuxedo I have has never bothered coral. I also have coralline that gets munched occasionally but think its more of the emerald crabs than the tuxedo.

A few other things I've noticed with my non-aggressive lps: they will turn pale in places where my goby leaves a pile of sand on them, and they are particularly sensitive to alk swings. Have you checked your alk recently?

FishyReef said:

If you think something is munching on it, I'm going to take a guess its the short-spine. They are reef-safe with caution and my purple short spine was the one who ate my coral. The tuxedo I have has never bothered coral. I also have coralline that gets munched occasionally but think its more of the emerald crabs than the tuxedo.

A few other things I've noticed with my non-aggressive lps: they will turn pale in places where my goby leaves a pile of sand on them, and they are particularly sensitive to alk swings. Have you checked your alk recently?

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No I haven't checked my alk lately. I will though tomorrow. What is the treatment for low alk? Also would that make it go from perfect to white in the middle and edge overnight?
Thanks

Angelajean said:

No I haven't checked my alk lately. I will though tomorrow. What is the treatment for low alk? Also would that make it go from perfect to white in the middle and edge overnight?
Thanks

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Checked my pH and it is 8.0. Ammonia 0, Nitrites 0, Nitrates 0. Salinity 1.025. Temp 78.

We are going to place the alien eye back in the main display tank near the bottom and do a night investigation. Black out the living room after dark and see if we see any culprits. We have a black flashlight and have done this before to see other things, like bristleworms and assessing how many snails we have etc. We keep a daily log for homeschooling on the tank.

Angelajean said:

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Hopefully here are the pics. What would have done this? Something has to have been munching on it.

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Okay so this piece is totally white now. My husband thinks he could possibly have done this as it was sitting right beside the zoas that have been infested with ugly palys. He was picking the palys with one of those grabber things and lots of them before they choke out our zoas. Could the toxins from the palys kill the chalice?