HELP! My Montis are dying???

[Ashmb56]

It was the day before a scheduled water change and I noticed my green montipora had basically changed within a day. It was fine in the morning and when I got home from work it looked like this. I recently dosed with reef Roids and that’s the only thing I’ve done differently.
What can I do to help them and reverse what’s been done. Any advice is welcome! Thank you!

 

[Flippers4pups]

What's your water parameters? Mine would pale, though not as bad, when my P04 bottomed out.

Is your light intensity the same?

 

[Ashmb56]

The lighting has never changed since I introduced them to the tank. They’ve been there for about 8 months and I’ve never seen them even get slightly pale.
I’ll test for PO4 and repeat a water change. Everything else is stable and has remained stable and thriving up until I dose with Reef Roids. So far none of my other corals are acting up.

 

[Ashmb56]

I’m sorry, *dosed is what I meant. Also it was the first time I’ve used this product.