Check the listing for details. Spa Marvel Filter Cleaner. Condition: New. Listed at 29.99 USD. DescriptionRemove odors and buildup that accumulate in the spa's filter that build up over time. This easy-to-use cleaner is powerful and removes oils, hair, dirt, and grime that is trapped in the filter causing unpleasant odors. Using this product on a regular basis will avoid odor problems in your cartridge filter without the use of bleach or harsh acids.How to Use Spa Marvel Filter CleanerRemove filters from spa.Add 2 capfuls of Spa Marvel Filter Cleaner to up to 20 liters (5 gallons) of fresh water in a pail.Soak filter overnight in the solution.Rinse debris from filter with a strong stream of fresh water. Showers and kitchen sink taps often do not provide enough pressure to remove deep-seated debris from the filters. If discoloration remains between the pleats of the filter after cleaning then the filter still contains debris. Stronger streams of water may be necessary. Pressure washing the filters works very well to remove deep-seated debris and will not tear the filters. If you do not have access to a pressure washer consider using the pressure washer at the coin-operated car wash.