Prima Replacement filter

According to original pattern of each cartridge filter to be replaced every 2 weeks. In my opinion, a cartridge holding but longer. I gather dirty cartridges, this sink with water and clean it gently between the fins with a soft nylon brush. Then I let the cartridge completely dry before used again. For this, of course, is an exchange with several cartridges in use, so that the pool water can be filtered at any time.
So I have the cartridge significantly longer in use, without it in my opinion on the quality of water has a negative impact.