Just started dosing kalk in my ATO calc was super high ~550s and alk was about 1-2DKH, i dosed quick to get it to be 12DKH and 500ppm for calc. Phew... Started the kalk yesterday at 1tsp/5 gal (29 gal tank ~25gal with rock and sand included) 5 tsp of kalk in my 5 gal freshwater reservoir. I cant wait to see where its at and hopefully that will lower my WC immensely.