I have a well established 75 gallon reef aquarium with a 20 gallon sump equipped with a protein skimmer and phosban reactor running. I do about a 20% water change weekly and the parameters are as follows: 1.024 salinity, 350 mg Calcium, 8.0 dKH alkalinity, 0 nitrates, 0 phosphates, 8.0 to 8.3...