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I have 3 zones running off 2-HP pump with bladder. 2 zones (7 heads each - all 1 inch line, Nelson gear driven) are at same elevation as pump (with anti-siphon control valves 1 foot above) and operate correctly; that is, pump runs continously at ~50 psi for duration of cycle.
Zone 3 (7 heads - Nelson, 1 inch line also) is at elevation 12 foot higher than pump/bladder. Anti siphon control valve is also 1 foot above this. Problem is when this zone is running, pressure at bladder increse dramatically and goes to shut off point (~ 60 psi) and then pump recycles. Pump on-off is not good. I think the solution is to "get more water thru this zone" - by adding more heads and/or larger nozzles. I have added 4-5 more heads - and increased the nozzles size with no success. I can change the pump shut off pressure valve to >60 psi but am hestitant to do this.
What might be a viable solution?

Thanks for the reply and input.
I do have "wiggle" room on the shut off - as I can go to 65-70 psi - but I am very hesitant to do this.
I understand about using the larger diameter pipe. Are you suggesting the entire zone be "repiped" to greater than the 1inch I currently have? Or just the supply portion to the anti-siphon control valves? Thanks again.