The Hayward does have that multiport valve so I was thinking of that, but it chews through water pretty fast, and our well is a low producer so I can't replace it as fast as its leaving. On top of that the pool is no longer level, so I can only overfill about 2" which buys me about 3-4 mins of backwash/vacuum action.

The pool was purchased in 1998 with this filter and pump combo, so maybe it is due. Not knowing the setup I crawled under the deck ( the pool has a deck built around it ) to put the head on the Hayward and there was no room to look inside once the plastic they had clamped in was off. I only later found they built a trap door in the deck so I can operate it from above. I'll have to check it out but I need to buy a plug for the skimmer and jet so water isn't flying out when I'm working on it. Its all about 4" below the bottom of the pool level so even with no pump powered on backwash water comes out at a decent rate so I imagine pulling the head off would result in some water flow. I don't see any sand on the pool bottom, only dead Algae.

Will a cartridge filter be better at it than sand? The 1000gph Intex cartridge/pump is only $68 here at walmart which seems fairly reasonable for a vacuum only setup that I can change easily when clogged.