Help! What happened??

[hopperjl16]

So you say Reef Builder to raise KH but you didn't mention Calcium. Both need to be balanced so any dosing to raise KH needs to be married to one that raises calcium as well.

The mistakes I see mirror many that I made. Trying to lower PO4 without knowing exactly what PO4 was can harm corals. If you had GHA odds are it was consuming most of the PO4. That said, Poly Filter doesn't move PO4 much so I'm not sure that's the issue. I suspect an Alk swing from too low to too high, which will knock out most SPS, quicker than most people think. I've been there and done that.

Use two part to modify params, measure KH, and dose equal parts two part based on KH needs.

Keep an eye on the top edge of your tank for new poci's to pop up, they rarely completely vanish, fortunately. They can reproduce via polyp bailout and show back up on tank walls, on the rocks, etc.

I'm thinking you're right with the alk swing. My PO4 were reading zero, calcium 420. PO4 low prob bc of the gha. I'm surpised i went from 3.0meq/L to 4.0meq/L in like 10 days. I wasn't expecting it to be 4.0 when I measured tonight. The last time I dosed the reef builder I don't think I had this coral. So far my montipora is ok.....

 

[markalot]

I'm thinking you're right with the alk swing. My PO4 were reading zero, calcium 420. PO4 low prob bc of the gha. I'm surpised i went from 3.0meq/L to 4.0meq/L in like 10 days. I wasn't expecting it to be 4.0 when I measured tonight. The last time I dosed the reef builder I don't think I had this coral. So far my montipora is ok.....

I never lost montis to an Alk swing, and some of my acros even survived, though had some significant dieback. The so called easier SPS like Pocis and a big beautiful green birdsnest just up and died in terrible dramatic fashion. It was shocking to say the least. I was able to save every poci either by fragging or finding a piece growing on the tank wall months later. Fingers crossed!

 

[rkpetersen]

I added a poly-filter 2 days ago to help me decrease phosphates (I have a gha issue - long standing, almost 6 months).

Poly-Filter would not have done anything like this, not a chance. It is a very gentle filter with virtually no detectable effect on calcium, alk, or Mg. Also doesn't particularly remove phosphates, but will adsorb organics which if then removed from the system help to hold phosphates in line.

 

[Mark Derail]

(keep in mind, a sw reefer for only 1.5 months)

I had similar happen to me, lost fish. QT the fish, and did daily 40-50% WCs, because when I tested for phosphate, it was above 0.5ppm - near 1ppm.

Many many WCs (daily for almost 10 days) to bring the phosphates to normal, to leech it out of the live rocks.

Since I've separated my fish from the corals, it's been easier to get things under control.