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From Unicel;For all spa cartridges and elements used in swimming pools where perspiration, suntan lotions, and other oils are present, soak the element for at least one hour (over night is more effective) in (1) a commercial filter cleaner; or (2) one cup trisodium phosphate (TSP) to five gallons water; or (3) once cup dishwasher detergent to five gallons of water.
Why does Hot Springs tell you to use the dish washer to clean their TriX filters... but not to use detergent? :-/
Why is it that Spa specific products tend to be so much more expensive than their non-spa equivalents?