What is kalk?

[junnie]

Can someone tell me what Kalk is and what it dose for your tank. I never put too much though in to it before. Should this be something I should do for my tank? Will it help in promoting growth in the tank? How dose it work?
Thank you.

 

[Woodstock]

Kalk is a German word for 'chalk'.... it is a extremely caustic calcium hydroxide powder and is sold under many different labels. When mixed with fresh water at a rate of 2-3 tsp/gal, it becomes a balanced ca/alk supplement! I use it for all evaporated top offs (1-2 gal per day) for my reef As with all supplements, testing prior to and after is recommended! In this case, testing for calcium and alkalinty.

First test your water to see if you even need to supplement... low ca? Most reefs do just fine with regular water changes to replenish the needed minerals.