[chocolateblnt]

I simply brought my calcium level to 420 mg/l, waited the period of how long it takes for my 5 gallon jug to empty which is 2 weeks* without adding calcium, calculated depletion and now I simply add the proper amount of R.A.C. every time I fill up my jug with RO ... since I haven't added/deducted inhabitants my calcium depletion stays regular. This is also more cost effective, $10 bucks does the calcium trick and will treat 2000 gallons. Never have to mix junk etc...

Everyone should worry about over dosing calcium because if you overdose then you're alkalinity will drop. If that happens you will actually precipitate out your calcium as calcium carbonate (Ca+). If you can't keep calcium and alk steady then the problem is magnesium interfering. But with Kalkwasser you not only have to worry about overdosing calcium but also overshooting pH. This is because carbonate can change into bicarbonate and vice versa... we want Ca++ which is a more readily available calcium which corals and other stuff can intake without expending a lot of energy to do so.

*once again from my previous post if you're not evaporating enough to supplement through kalkwasser then your kalkwasser is useless. I was evaporating enough however I plan on stocking the tank heavily with corals and once that happens I probably won't be. I went through this before when deciding on top-off system whether to go kalkwasser or just simple top off with calcium supplement.