Never listed what your po4 is at

unimportant. Algae food mostly.

I would disagree. I've lost lps of that sort from to high of phospate

I highly doubt it was the PO4 that caused your issues. Just saying.

Anyhow, not going to argue over it, in two hours there is no way PO4 is the culprit.

Nor will I argue but this is out of a artical from reef builder

Besides fueling algae growth, phosphates can retard the uptake of calcium by calcifying corals. This of course is bad news for reef keeping aquarists who house a lot of hard corals. The corals will slow their growth rates as phosphate concentration rises. Some may even begin to die or have tissue recession. The latter part is obviously an extreme case, but it can happen when phosphates reach higher concentrations. A slowed calcification not only means slow growth, but slow repair when damaged by fragging or hands moving about the aquarium.

Yup. I know this. But it will not kill a coral in two hours. Think of other corals in the tank.

It's not the po4.

Good luck! Signing off.

Did not see the two hour part pat

My bad

No worries.

Good point on the ph...

Was much higher when the first ones went in(8.2)

Now it's declined. I've been dosing now and just bought a calc reactor.

I'll hold off till I get my ph up the. Try again. I'll update once I do!

Thanks so much for the help!