Kalkwasser - Translates from the German for limewater and is a solution made by dissolving Calcium Hydroxide in water. The resultant fresh solution is alkaline with a pH of 12.4 and contains a ready supply of both Calcium ions and Carbonate ions.
The solution reacts readily with CO2 in the atmosphere to form calcium carbonate and so it must be made in a relatively air tight environment which is where the kalkwasser stirrer comes in to play.
The KM500T is the standard stirrer suitable for tanks up to 1500 lts - 350 UK gallons - 400 USG and will produce up to 5lt - 1.3 US Gallons of kalkwasser per hour.