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I would disregard anything that guy told you.MPS has no sanitizing abilities. Without a sanitizer like dichlor or bromine, you will end up with a tub full of bacteria, so keep the dichlor in your routine. Regarding your routine, I'm not very comfortable with using dichlor only as needed. IMO it should be used prophylatically. Most of the users here add a little after each use. Search "dichlor" here or see the Vermonter post in the FAQ of the rhtubs.com site for a good discussion on santitation. Some brands of MPS are pure, others have buffers to counteract the low pH, others are combined with dichlor to create an "enhanced shock". If your Leslies MPS has the same ingredients as the HS version, it will work the same.