I'm a new pool owner. I had a pool inspection done and they noted in the report that my filter is a "Premier DE no backwash type." Looking for some guidance on whether to backwash or not. Of course the inspection folks want to me to fork out more money to come out and give me more info.
More background info that might be relevant: based on the construction docs I have, the pool was built in 1979, and the filter has 72 sqft of cleaning surface area. Some additional notes indicate 138 GPM flow rate (not sure if that's a pump number or a filter stat or something to do with the pool pipes).
Attached is a photo of the 30-year old filter cleaning instructions I inherited.