dying favia

Hello. I have no idea why my favia frags won’t grow. I’ve had my tank for about 7 months and here are my current parameters: Ammonia: 0 ppm Calcium : 430 ppm Nitrate: 2 ppm Nitrite: 0 ppm pH: 8.0 pH Phosphate: .50 ppm Salinity: 1.025 SG I haven’t tried testing alkalinity or magnesium yet. Would...