My filter manual recommends cleaning the filter when the pressure rises 10 PSI higher than it did when the filter was first installed. The pollen level has dropped off in my area so I opened the cartridge up recently and hosed it down even though the pressure wasn't up at all. I read that it's easier to clean the cartridge more frequently than to wait until the pressure goes up.

I highly recommend using a scum sock as that kept a lot of junk from getting to filter and I clean & rinse that out at least once a day.

I know what you mean as we've had crappy weather in the northeast too for this time of year. Hopefully things will change soon for you.

Peter