I purchased a trachyphyllia about six weeks ago and there is a bleached patch that has been slowly expanding over the last couple weeks. I had a problem with Aquavitro Salinity salt and my alk was down around 4.3 dKH. I bought a new test kit and confirmed it was accurate. I already lost a huge stylo that I grew out from a frag to RTN and I don't want to lose this coral too. I have raised my dKH to 9.0 over the past week but the bleached patch is still growing. I vodka dose so I don't want to go much higher. I also dipped it in CoralRx last Sunday. It still expands well at feeding time and happily eats if I target feed. The bleached area does not expand as well but there is no skeleton showing. Here are my current parameters pH - 8.2 Ca - 400 Mg - 1350 dKH - 9.0 Phosphate - 0-.04 depending on when I check it Nitrate - 0 Nitrite - 0 Ammonia - 0 sg - 1.025 Temp - 78 Any advice on how to proceed is greatly appreciated. I'm starting to panic. Here are a couple pictures. Sorry for the white balance quality but I used my phone.