Hi currently my new tank is up for 4 months. I am having zero nitrates in my tank recently. My Cal is 420ppm…Mag is 1500ppm…PO4 is 0.02 ppm…kh 8.9dkh..i have not been changing water for a month as my nitrate is 0…I have about 6 fishes and 2 corals and all are doing well…i have been dosing KH,Cal and Mag…My sand bed has diatoms…I wan your help in this…Should i raise my nitrate ? should i do a water change ? Should i stir the sand bed ? Any help will be very helpful…i tried dosing neonitrate to .5ppm but it went to 0 after 24hr…my rocks has brown stains and abit turing green…. Thank you in advance Sent from Singapore Reef Club mobile app