Am I killing my Zoa?

[EEE1986]

Hello,
I purchased a candy apple zoanthid about a week ago that was doing great in the original part of the tank I placed it (See before picture). Yesterday I moved the frag to the opposite side of the tank to a rock island I thought would be more suitable (less PAR, better flow) but It seems to to have ticked it off because only 2 polyps have unfurled since and they occasionally are making umbrella shapes. They also seem more outstretched as of today. When I moved my frogspawn coral last week to that same side of the tank from its original site on the opposite side where it was presumably doing well it subsequently melted away within a few days so I am paranoid this is going to happen to my zoa. The parameters I measured yesterday before performing a 20% water change were as follows (Nutrients were higher than average I presume due to the frog spawn mortality. A testing kit for Ca, Mg, KH is on its way but I was not as concerned about these values due to low amounts of coral in my tank and them being mostly soft):
Nitrate- 10 (Usually 5)
pH- 7.8 (Usually 8)
Phosphate- 0.25 (usually 0.125)
Salinity-1.027
Temp- 76-78F

I perform weekly 10% water changes with Imagitarium Pacific Ocean Water from Petco.

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Other coral species I have in my tank are GSP, pulsing xenia (Also not looking as lush since I moved it to the back of the tank yesterday), a tiny montipora digitata frag that I accidentally split in two when trying to remove from the frag disc but both segments seem to be doing okay, and some random palythoas that grew from the live rock. All of these other corals seem to be stable and growing. Is my zoa just acclimating to the new spot and needs more time or should I move it ASAP?

 

[ColorMeGone]

I would give it a bit of time or maybe give it a check over to see if something is bothering it. I had one do this a few weeks ago and dipped it in SeaChem and gave it a dip in peroxide also. Back to normal now.

 

[EEE1986]

I would give it a bit of time or maybe give it a check over to see if something is bothering it. I had one do this a few weeks ago and dipped it in SeaChem and gave it a dip in peroxide also. Back to normal now.

It was completely fine on the other side of the tank though and I dipped it prior to adding it. The one thing that may be bothering it is my black spined sea urchin who keeps on feeding on top/around it. I'm gonna get rid of that thing anyway as it's gotten too big for the tank but the coral is only looking worse now two days in to relocation.

 

[ColorMeGone]

It was completely fine on the other side of the tank though and I dipped it prior to adding it. The one thing that may be bothering it is my black spined sea urchin who keeps on feeding on top/around it. I'm gonna get rid of that thing anyway as it's gotten too big for the tank but the coral is only looking worse now two days in to relocation.

I don't know a thing about urchins but if it's all over it this could be the problem.
My snails are the only thing that make my Zoes close up but once they pass by, they are in full bloom again.

 

[Mr. Mojo Rising]

That picture of the zoa's shows them in the shade, they need light.

 

[EEE1986]

That picture of the zoa's shows them in the shade, they need light

They are getting plenty of light. If anything, they are getting more light than they were in the original position.

 

[EEE1986]

Update: All polyps closed and the one that remained opened is slowly melting away. The closed polyps are starting to grow algae on them. I got rid of the sea urchin but the problem persists. Finally bought a trace mineral testing kit and my parameters were as follows:
Salinity: 1.027-1.028
Ca 360
KH 8.4
Mg 1170
Nitrate 10
pH 8.0
Phosphate 0.05
LFS seemed to suspect Mg being the problem so I have been dosing that with the Red Sea product for the last 3 days. One of the Polyps opened today but the rest seem to be degrading. Just performed a 15 min dip tonight with Revive as well (Let me know if there is a different product I should have used). If this doesn't work I don't know what else to do.

 

[Tahoe61]

At this point I would be tempted to look at Lugals Iodine, and or supplements with potassium. Research the use of vitamins C. Test for iodine and consider sending in an ICP.

 

[Patx]

We don't (i never find "the real reason") really know why some zoa or paly melt.
May be "bacterial infection" could be numerous thing.

Try dip in peroxyde/water or dip in iodine.

 

[ColorMeGone]

I use SeaChem dip that has Iodine in it. A peroxide dip wouldn't hurt either.
I do 80% tank water to 20% peroxide for 2-3 minutes.

 

[BryanM]

I would have, or still would move it back.

 

[EEE1986]

At this point I would be tempted to look at Lugals Iodine, and or supplements with potassium. Research the use of vitamins C. Test for iodine and consider sending in an ICP.

Even though all other corals in the tank are doing fine?

 

[ChrisfromBrick]

takes a lot to kill a zoa

 

[EEE1986]

I use SeaChem dip that has Iodine in it. A peroxide dip wouldn't hurt either.
I do 80% tank water to 20% peroxide for 2-3 minutes.

I was deciding between Revive and Seachem iodine last night because I happen to have both but decided to go with the Revive becauses it seems to be less harsh on them. I would try the iodine now but I'm afraid to dip twice in 24 hours out of fear of doing more damage than good from stressing the coral.

 

[Shirak]

I'm going with @Mr. Mojo Rising Not enough light. I think you kind of answered that in your OP. You moved them from an area they were doing well to an area which has less par and observed them staying closed and "seem more outstretched". If the biggest change was a drop in par then that is your answer. The most sensible thing would be to put them back where they were doing well in the first place. If you want to keep it on the rock then move the whole rock. You could also slide the rock over on the sand bed towards the middle of the tank.

As for your lighting on the tank:
Settings on your AI Prime? I have one on a 5g tank and my zoa are nearly directly under it. Light is about 10" off the water and the zoa are about 8" below the water. Light is running at 80% intensity for most of the day. UV, Violet, RBlue, Blue primarily. Tiny bit of red. green and white.

The other thing with the AI Prime is the spread is terrible. Where you have the zoa positioned is outside the spread of the light. You can see it in the picture with the blue cone on the wall where the brighter cone shaped area is. The light is also angled slightly downward in the front, so the light is projecting more towards the left side opposite where the zoa are. The par levels from an AI Prime drop off drastically the further outwards you move from the center of the light.

Long term I think you need to look at a lighting upgrade. A single AI Prime on a square tank that size is not going to give good coverage.