Hi all. I used baking soda to raise my KH but now my PH is at 9.0. When I first did the baking soda my PH went up to the 8.4-8.6 range from 8.0. I've read where calcium chloride will lower the PH to 8.3 if baking soda has been used to raise the KH. My questions are what and where do I get calcium chloride( is it a salt?) and how much to use per 1000 gallons?