I have zoas and SPS in my tank. When my nitrate was 1ppm and phosphate 0.40ppm, my zoas were all thriving. Since I have SPS in the tank so I started running nitrate sponge. Now my nitrate is all 0, but my zoas are getting skinniest and eventually melt. Any ways to improve? I run a calcium reactor and chiller so my water cemestry and temperture are stable. Should I feed agreesively? Thanks for any feedback!