If I use the 3 rule test for determining safe flow, rule one (10% max. psi loss through meter) for a 5/8" meter limits the gpm to 13, and the limit is 15 gpm for rule 2 (75% of max. safe flow, which is 20 gpm), so if the new irrigation meter is 5/8", those two rules I think would still apply, so perhaps it could raise the max gpm to 13? If we ignore the 3 rule test and look at the bucket/pressure loss test, would you be referring to the following test? Thanks

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