Background: I have a 110 Reef Tank with hard and soft corals and a few fish, refugium with lights, Protein Skimmer and a Current Outer Orbit light fixture with 2 x 250 10K HQI-MH + 4 x 54 watt T5 HOs and 18 lunar leds. Chiller set at 79 degrees F and a lot of patience! haha Tuesday: Calcium: 440 Magnesium: 1225 PH: 8.4 dkh:20 ? kh is off the chart. Frequent water changes, have no effect so how do I lower kh without crashing the other levels? Do I need a chemist? UPDATE AS OF 1/30/2009 21:25 EST Good News / Bad News FYI - I am using three stage RO water so that is not the problem. I bought new API test kits for Ca, Kh, Ph and Mg. As of the last three days the Kh has dropped so is the calcium. I have been dosing with DT's Pure Reef Calcium. Here are the readings and doses last three nights in a row: Wednesday: Ca 360 dKh 15 Mg 1230 Ph 8.4 I added 50 ml DT's Pure Reef Elements Ca Thursday: Ca 360 dKh 14 Mg 1225 Ph 8.4 I added 100ml DT's Pure Reef Elements Ca Friday: (Tonight) Ca 360 dKh 13 Mg 1200 Ph 8.4 I added 150 ml DT's Pure Reef Elements Ca What does everyone recommend?