Kalkwasser Calcium hydroxide supplement for coral 4.5kg

Kalkwasser is a calcium hydroxide supplement to help corals grow and build coral bone structure. Unlike many other brands, thisproduct is finely ground to maximise solubility.  Keep adding Kalkwasser powder to 2 litres of water until no more can be dissolved. Then over a few hours, add solution to the aquarium very slowly (using a drop system into a moving current).