My pool has a Hayward filter. I am using a Unicel filter and the pressure is getting close to 20 after running the pump for a couple of days. I bought this filter about 11 months ago. Most of the time, I spray down the filter every week or so. I was curious as to what the average life is for a cartridge filter? Is Unicel any good or should I buy a Hayward filter? Thanks in advance.