With my single MES membrane running at 225 psi and 39-40 F degree sap I max out at 1 gpm of permeate and I run the concentrate at 0.5 gpm.
Depending on your sap temperature you will get different results. The rejection rate goes down with colder sap.
Do you have a recirc loop?
Flowmeters.
And as the membrane gets more sap through it it gets less efficient.
I found after 750-1000 gallons processed it needs a good soap wash.
600 taps on vacuum
Lapierre mechanical Releaser
CDL electric releaser
2.5 x 10 CDL Venturi ( new for the 2024 season )
Home made modulating auto draw off
Homemade RO 2 x 4" membranes
CDL 16 x 16 bottler
Wesfab 7" filter press
Delaval 73 vacuum pumps
12 hives of bees