SPS / Phosphate Question - Help!

[BrianReefer]

I have a year old tank with lots of SPS, mostly frags and mini colonies that have grown out over the year. All was well until one of the green tenius’s starting fading. Then it totally bleached. I have an Alkatronic and APEX, so alkalinity, PH, temp, all good. I was lax on testing phosphate out of laziness and no issues before. I tested calcium which read fine.

Fast forward. My Red Sea calcium test was old and giving a false reading. It said 450 for what was really 550 ish. Phosphate got pretty high, probably around 1 at its peak.

I started to reduce the calcium over a few days and got it back to the 450 range. phosphates we’re reduced via GFO + algae reactor over a few days down to .03-.04 range.

Since then that green tenius started to get color back. But sadly a few of my SPS just turned to skeleton, and I’m hoping a few others that bleached come back.

Anything else I should be doing to help them recover? Is it likely that the calcium +/or Phosphate spike caused this? I’m assuming it was the latter and that I should just focus on stability and hope for the best, but would love any other suggestions!!

 

[Charlie’s Frags]

It was most likely bringing po4 down too fast with the gfo

 

[bobby.w.hodges]

Nothing good happens fast in this hobby

 

[BrianReefer]

It was a lose/lose, since they were bleaching and dying with the phosphates where they were, but I didn’t think going from ~1 to .05 over a week was that drastic...??

 

[Charlie’s Frags]

It was a lose/lose, since they were bleaching and dying with the phosphates where they were, but I didn’t think going from ~1 to .05 over a week was that drastic...??

1.0 to 0.50 would of probably been ok, but 1.0 to 0.05 is a huge change

 

[BrianReefer]

1.0 to 0.50 would of probably been ok, but 1.0 to 0.05 is a huge change

Ahh my mistake. I was around 35 on the Hanna Phosphorous tester, so that’s a typo, I was .1.

So I went from .1 to .05 in about a week. Would that change do it? But change aside, even the .1 shouldn’t have caused so many issues with my SPS no? Can’t figure out what else was the cause of the original issue after such long stability.

 

[bobby.w.hodges]

Have you actually tested your other parameters, or are you just assuming they are stable due to the alkatronic?

 

[BrianReefer]

Tested them all and had an ICP water test last week and everything came back fine, including Phosphate since it was 2 weeks after the GFO. Aluminum was a bit high because I did use Phosguard at first while i was waiting for the GFO. But everything else was in normal range. I also have an AWC system setup exchanging 3g/day on my 116g tank so always getting fresh supply of Tropic Marin Pro in there. Any other ideas of what could be the cause, or think mostly likely suspect was the slightly elevated Phosphate?