i have been seeing a pressure rise in my filter cartridge of 15 PSI in only 24 hours of run time. When I shock the pool or have higher loads on the filter it can last as little as 8 hours. When I soak the cartridge in dish soap and water, I spray it off with a water stream. The solids coming off of the filter looks like Brown sand. I assume this is related to Algae being filtered out, but not sure.
When I put clean filters in the pressure is 13 psi and then I change the filter when it gets to 25. The filters never look too dirty, but it is hard to tell for fine dirt. Is now a good time to try and acid wash as the filters are at the end of their life anyway or is there something I can try to get a longer run rate from them? There are 4 80sq ft cartridge. I'm not sure if they are sized appropriately o not, but they are the originals with the house I bought so it was the designed filter.