For whatever reason, the leaves do not back flush out. I see maybe a few hundred in a full backwash, with thousands upon thousands staying inside. Since we put the sock in-line for the vac, I back-flush about once every 3 weeks outside the heavy leaf seasons (spring/fall), and probably 1.5 weeks during. I just go by the pressure as directed by the local pool equipment guy (not a cleaner). He seems to be ok, once I finally got one who didn't seem like a complete idiot (like the first 2).

As for size, he says it and the whole system are "adequate". To paraphrase, he said something like "It is sized a maybe bit on the shy side for a 25k diving pool, but it will do the job when running right. He was the first to show me how to manually service the filter, what too look for, and what to be careful of damaging (the laterals). His number 1 suggestion, obviously, was to "get over it and get rid of that tree". Still not on board yet, but I did have a tree guy climb up through it and "open it up". Now looks sorta like something you would see on the African Savannah, and LOTS less mess than the first spring.

The back was line is all exposed 2" PVC. There is a single "street bend" 90, and then 2 45s to get is relatively horizontal and low to the ground, followed by 2 10' sections end to end to get clear of the "pump area". From there I put a 25' 2" roll up on to get the water to a tree basin so that I get SOME use from all the wasted water. Tree (elm I think?) seems quite happy. Flow seems huge to me, and I had to construct a dispersion pad from block to keep from starting an open pit mine every time I back flush. I could back-flush 2k gallons and still not do much against the accumulation of those blasted little leaves. And I'm not kidding about the volume. Early on, in desperation before just accepting the manual clean out, I let it run a LONG time. Long after the water ran clear, dropping water level enough that the skimmer was sucking air, and still had about 2 gallons of leaf mush (almost like clay in parts) to remove by hand.