help scoly

Hello all, I have had a Red Scoly that was living life, fat and happy. Though today I noticed that it had black marks all over it and is retracted. Some additional information: Salinity: 1.026 Phosphate: 0.1 Nitrate: 20 Calcium: 400 Alk: 9 Mg: 1250. Last week I did add an AI Blade to my...

I am not sure but it looks sexy shrimps are eating my breeding apple scoly... Any advice on how to save my scoly? Five sexy shrimps in 13.5G tank. No fish. Water parameter is normal and stable: Alkalinity 7.8, No3 11.2ppm, Po4 0.08ppm Feeding coral food to scoly: Once every 5 days So far, I...