FIlter Pressure keeps changing

[sincityharley]

I have a DE filter that filters my pool and spa. I just bought the house so I cant tell you what happened to this filter. The thing is though I just cleaned the filter out completely wtih a hose. I did notice a tear in one of the fins. Its a DE filter that uses a cartridge like filter. After I clean the filter or do a backwash I get awesome suction from the pool cleaner. The filter is showing a 10 right after cleaning. After just one day of running my filter now shows a 20 and there is less suction. After tomorrow the needle with top out around 25 - 30 and there will be a very light suction that is pointless, it wont even move the cleaner around the pool. Does anyone know why this happens? What can I do to solve this problem? Thanks in advance