Yellow Polyp Mayhem!

[Biofreak]

Have yellow polyps with about 20 heads. They were doing well for a few months, but recently a few of them are shriveling up and turning brown.
Phosphates.05
Nitrate-0
Ammonia-0
Kh-10
Cal-450
Ph-8.2
Salinity-.25
I have a few theories, but being a noob to sw I was looking for some feedback from the experts!
Some things that might help you help me: About 1 week ago upgraded the 29biocube to led. 1-50/50- 1-12k- 1-actinic (ecoxotic panorama pro strips)
I have also been dosing the reef booster vials w/o testing my stronium, iodine levels.(maybe I od'd them lol)using 1 of each per week, which is the recommended dose.
Have a coral beauty that grazes around the polyps, but have not seen him pick at the polyps themselves.
I do occasionally see the cleaner shrimp try to steal food that the polyps catch.
I feed once a week the coral food mix, but don't target feed just brodcast the tank for the other corals.
About a week ago I moved the fan to redirect the current and the polyps no longer receive the brunt the flow.
Recently added phoslock to my filter media.(could it leach?)
All other corals are thriveing and looking really healthy finger leather, gsp, toadsool leather, frogspawn etc..
Anything y'all can think of for me to check? Or anything I listed a potential problem? Thanks!!

[Scott Allen]

Have yellow polyps with about 20 heads. They were doing well for a few months, but recently a few of them are shriveling up and turning brown.
Phosphates.05
Nitrate-0
Ammonia-0
Kh-10
Cal-450
Ph-8.2
Salinity-.25
I have a few theories, but being a noob to sw I was looking for some feedback from the experts!
Some things that might help you help me: About 1 week ago upgraded the 29biocube to led. 1-50/50- 1-12k- 1-actinic (ecoxotic panorama pro strips)
I have also been dosing the reef booster vials w/o testing my stronium, iodine levels.(maybe I od'd them lol)using 1 of each per week, which is the recommended dose.
Have a coral beauty that grazes around the polyps, but have not seen him pick at the polyps themselves.
I do occasionally see the cleaner shrimp try to steal food that the polyps catch.
I feed once a week the coral food mix, but don't target feed just brodcast the tank for the other corals.
About a week ago I moved the fan to redirect the current and the polyps no longer receive the brunt the flow.
Recently added phoslock to my filter media.(could it leach?)
All other corals are thriveing and looking really healthy finger leather, gsp, toadsool leather, frogspawn etc..
Anything y'all can think of for me to check? Or anything I listed a potential problem? Thanks!!

The lights are the most likely culprit. Your new lighting is much much more powerful. Turn down the photoperiod and slowly build back up to current. (or try moving the zoas to a more shaded area) Do you have a pic of them?

STOP dosing things you don't test for. There is really no chance that you need to be dosing iodine or strontium. You will crash your tank dosing stuff like that. Keep to calcium, alk, magnesium and food. There is no reason to dose a 29 gal with anything else. Water changes will fully replenish any and all trace elements.

[Biofreak]

Ok not the best pic, but had to use my phone. The one on the top right, stalk is laying against the rock. Before he was nice and streched out into the water. Also hard to see but on the right side of the rock most of them are closed or shriveling up. Some have began to turn a darker brown than the rest of them. Thanks for the help. I will quit dosing the rest and only monitor my cal, mag, etc.. I am also going to lower them in the tank and have set my timer on the lights back 3 hours and dimmed them a little with an in line dimmer.

[Scott Allen]

Ok not the best pic, but had to use my phone. The one on the top right, stalk is laying against the rock. Before he was nice and streched out into the water. Also hard to see but on the right side of the rock most of them are closed or shriveling up. Some have began to turn a darker brown than the rest of them. Thanks for the help. I will quit dosing the rest and only monitor my cal, mag, etc.. I am also going to lower them in the tank and have set my timer on the lights back 3 hours and dimmed them a little with an in line dimmer.

Sounds like a great plan! If you keep the water clean and cal/alk/mag stable your tank will look amazing! Those are cool looking polyps!