Montipora specific bleaching

[Decadence]

I'm having an issue with jus about all of my montipora corals while all of my acropora colonies look fine. The affected montipora are mostly caps while a few encrusting montipora and montipora digitata are affected. The base problem is that they have lost color over the course of a week roughly. The color is shifting to white, not brown. It seams to have started last weekend. In the last few days, I actually lost a little flesh on my reeftek starburst cap but it doesn't seam to be continuing.

SG: 1.025
PH 8.3
Temp 79.1
Cal 460ppm
Alk 8.3dkh
Mag 1450ppm
K+ 430ppm
No3 <1ppm
Po4 <0.015ppm

Around the time that colors started to fade, I did a water change using a salt which I have used for a couple months but changed more than I previously had as it was my first time using a new LDPE trash can which I cleaned prior to using. I had done my eighth dose of algaefix. I bumped my vinegar dosage up by 5ml to a daily dosage of 45ml spread over 24 hours. I was steadily increasing my light. The only other change made at that time was the addition of aquavitro fuel to a doser.

I dose iron and am currently deficient. I started iodine a few days ago and was likely deficient. I brought up a potassium deficient over the course of a few months and shut off my doser now that it is high. I dose magnesium sulfate/chloride and stepped down my daily dosage. I dose vinegar into my kalk stirrer to supersaturate it. I run a calcium reactor. I dose a small amount of superbuffer dkh from time to time to offset the very high calcium level of my salt mix. I have been using algaefix to combat ghost algae after four months of heavy nutrient control only seamed to make it worse. it trapped detritus and fed itself an there are too many acro colonies to remove the rocks. In those four months, every type of macro algae I had starved of nutrients and died.

Tank is a 90g BB display with roughly 20 gallons of sump, reef octopus EXT200skimmer w/ BB hy3000s pump, GFO and roughly 110x flow in the display with four vortechs and the return pump. Lights are 270w of full spectrum LED plus 78w of T5 with ATI blue+ and purple+ bulbs.

Part of me wants to believe it is too low of nutrients now that the ghost algae is gone and detritus doesn't accumulate anywhere. Part of me wants to think that the lighting is just too strong now that carbon dosing has made the water extra clear with all of the ghost algae gone. Part of me wants to think that high potassium is causing the problem though it isn't very high. There have been no known spikes in any parameters

What do you guys think?

 

[Prochef176]

Any signs of nudis? Usually underneath, little white frilly slugs.

 

[Decadence]

Any signs of nudis? Usually underneath, little white frilly slugs.

I searched pretty extensively for monti eating nudis but was unable to find any. I used to have black bugs but my sixline ate them all after he wiped out the red bugs on my acros. I only have missing tissue on one spot of one coral: the reeftek starburst cap.

The biggest losses of color have been with my encrusting green monti which started off as a frag and is now 6" across, my starburst cap and my Idaho grape cap. Last night, I found a mini brittle on the cap which has lost a small amount of flesh and it was in the area with the missing flesh. I have a lot of these stars.

 

[Prochef176]

Do you have any pictures of the corals?

 

[ostrow]

Bust off an affected piece and drop in RO water in a tupperware. That is how you find out if nudis....

 

[Decadence]

I have inspected very thoroughly for nudis. It was also quite a few corals simultaneously which we're thriving before. All-in-all, nudis seam very unlikely, though I am still searching for them at night and during the day. The one area with lost tissue does not look like a pest issue, rather stress.

I'll take some pictures tonight and post them, my cell pictures are nothing but blue. My dslr doesn't do great with white balance either so I will try to edit the colors as close as possible.