Tank still not doing well is it possibly chemical warfare?

[srad750c]

What's NO3 and PO4 levels, if they are very low, you corals will die off slowly. You need amino acids if NO3 and PO4 are low, add small doses at a time and I wouldn't change more than 5% of water weekly. I went through this problem, took me forever to find out about ULN(ultra low nutrient) tanks. Didn't know that was a problem. Read some of those posts, they will save you a lot of headaches.

 

[chromis]

What you are describing makes me wonder if your lighting is too intense, from the pattern of SPS slowly turning white from the top down. People run into this a lot with Kessils because they are such powerful lights. Sorry if I missed it but did you share your light setup and intensity setting? Your water parameters sound great, keep up the good work there!