I'm gunna have to start dosing for nitrates I guess.Seeing that phosphate has risen while nitrates have fallen, the corals are likely starving from the lack of nutrients, and the high phosphates will cause the corals to brown out. You’ll want to dose nitrate to gradually get the levels back up (I had made a sodium nitrate solution that I dosed at 5 mL a day until the levels rose). Once nitrate goes up, use water changes and phosguard to bring both back down slowly. If you try to lower phosphate before dosing nitrate, the problem will likely persist and your corals will continue to bleach/starve.
Do you have fish in the tank? Because the phosphate/nitrate problem happened for me when I didn’t have fish, and I had to dose nitrate to compensate for the lack of fish. Once I had a good fish population I was able to stop dosing nitrate. I still do regular water changes because phosphate will occasionally leech into the tank from my rocks.
I don't have any fish in the system well sorry I have one measly file fish. Unfortunately I had ich wipe out a bunch of fish I had almost 4 months ago and I haven't bought anymore and would much rather not buy any I really don't like the fish aspect of saltwater and want to stray far away from it. Oddly enough my file fish is still alive and doing fine some how.