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The filters are in the water and your water is supposed to sanitized so what is the point. I like Microban in the shells as it can help a little above the water line but it seems a little silly to me in a filter.
It's not a Microban product. This filter has nothing to do with the antibacterial product found in Microban. The MicroPure filter is a disposable 1 micron filter. It will not assist with the sanitation of your tub.