PURE CALCIUM At times the calcium demand by all the corals and the calcareous algae exceeds what limewater (Kalkwasser) can supply. This is not unusual in tanks where many coraline algae grow and where many hard corals are kept. When such is the case, hobbyists need to supplement their limewater with a calcium compound to make it more potent. Calcium chloride is not the right way to go because it gradually skews the ionic balance of the water too heavily towards the chlorides. Also, it is very easy to overdose with calcium chloride. Thiel Aqua Tech, Inc. researched many other calcium compounds that dissolved easily and were potent--i.e. they added a substantial amount of calcium to the water, enabling the hobbyist to maintain the desired concentrations of 450 to 500 ppm. at all times. Pure Calcium is such a product. Add a few crystals to your limewater and see the difference, or test for it! Your calcium levels will remain where you want them to be each time you use your newly prepared limewater to which Pure Calcium has been added. Sold in containers holding 50 grams which will allow you to treat about 150 gallons of a Kalkwasser. Thiel Aqua Tech Inc. (505) 526 4000 or call (800) 901 FISH