Just a quick note to anyone reading this and thinking "To complicated/expensive to do". Although the materials and methods here are spot on, this is what I've been doing for the last ten years. Mix up Kalk powder with dechlorinated water, 2 teaspoons per gallon. RO/DI water is ideal, but have used regular tap water with no ill effects, I've always used a PO4 remover anyways and with the amount of live rock I have nitrates are rarely an issue. I use a 4 gallon water cooler jug with a spigot on the bottom, its about 1-2 inches above the actual bottom of the jug. Add Kalk, shake the crap out of the cooler and let sit for atleast 12 hours. Get a dosing container, I happen to use one made by Kent with the simple gravity drip control thingy like the hospitals use. They have 3-4 sizes to choose from. After 12 hours tap the first liter or so and throw out. My drip container is 1 liter so I add 3-5mls of white distilled vineger to it and fill up to a liter of kalkwasser. This accomplishes a couple things, vinegar provides an equivalent of all the CO2 you need to avoid precipitating the newly-added calcium ions as calcium carbonate powder. Also the leftover acetate ions from the broken-down vinegar leave you with free organic carbon in the water if your interested in carbon dosing to further break nitrates down to nitrogen gas. Some people recommend dissolving the kalk in the vinegar first but I've found that leaves to much of a calcium carbonate scum, mixing the kalk then adding the vinegar when you dose avoids this. I have this hanging over the return portion of my sump and set it to drip so that it takes 2-3 hours for the liter to empty. I have nice coral growth, used to have 3 dinner-plate size pieces of montpora until I lost power late October for 48 hours and lost all but a quarter size piece that is presently regrowing. Got smart and bought a portable generator after that.
Like I said, the materials and methods already discussed in this thread are spot on, but if you have a smaller system or aren't into spending any more than you have to on reactors and such, there is a low-tech, low-cost method of dosing Kalkwasser that is also effective. My alk is around 180 ppm and calcium 450 ppm in a 65 gallon system. pH stays around 8.2-8.3.
Like I said, the materials and methods already discussed in this thread are spot on, but if you have a smaller system or aren't into spending any more than you have to on reactors and such, there is a low-tech, low-cost method of dosing Kalkwasser that is also effective. My alk is around 180 ppm and calcium 450 ppm in a 65 gallon system. pH stays around 8.2-8.3.