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From the manufacturer:
Twin pack of filter cartridges for the Intex Purespa.
Filter cartridges must be changed / cleaned regularly so that maximum filtration efficiency can be achieved. One method of managing filter cartridges is the rotation method, please read below for details on how to use this method.
Clean the filter every two weeks
Check your spa manual for the manufacturers instructions on how to remove your filter
Removal of physical debris should be done using water pressure either from a hose or a specialised cartridge cleaning tool
Before refitting the cartridge, always rinse and dry thoroughly
