Thanks for responding, I was just wondering why they would list it like that if it is not possible. The site is owned by Dr. Foster's and is pretty reputable. I just figured I would ask to see if I was missing something. I know you need at least 3 KH (API test) to have a stable pH without swings. I am at a loss, lol. I would understand if it was GH but I have no idea what they mean and was just curious if anyone else knew.