No water changes in 2 months. My Nitrates are steady at 0.5 ppm, Phosphate: 0.03 ppm (red sea and hanna ULR phosphorus), I recently went from Radion G3Pros to G4Pros but don't think that really did much. I also have two sets of T5s as well. I added me amino acids for the last couple months and NOPOX as well. I don't think the me amino acids are doing a lot but not sure. The NOPOX is helping control nitrates well. I have 20 fish so quite a high bio-load. I starting using my UV sterilizer regularly 1/2 of the day during the day. ORP used to be 250-300 and is not 400-450 so that's one big change that may have helped a lot. Lastly I started dosing kalkwasser instead of 2 part solution and that seems to be when I saw the biggest changes. I also add coral colors to replenish trace minerals.