MDR - sorry never posted the results from running both systems last year. The 6 x 150gpd system worked flawlessly I put about 2,000 gallons of sap through it over the course of the season. My sap was running around 1.3% and I was concentrating to around 7.5% and was processing about about 9-10 gallons per hour through the system. I was able to remove 84% of the water in a single pass. This was also the first year I was using RO soap instead of Hydrogen Peroxide. I did a wash after each run and found that there was no loss in performance over the entire season. If your sap is more around 2% I would only go with 5 membranes. My system with 3 x 400gpd membranes did not do as well. I had it plumbed with 3/8" tubing throughout and although was able to concentrate to the same level 7.5% but the rate of process was not as fast with only about 7-8 gallons per hour. However, I lent it to a friend who was swimming in sap and had him set it so that it was a 50 - 50 permeate to concentrate. This worked extremely well and allowed him to process between 250-300 gallons per day which was perfect for his needs. I think the larger membranes need a higher flow. As for mounting your system to a board it will make things a lot easier to work on. Last year I put mine together on casters which still allowed for easy access but took up less area and made it easier to move around. I will be posting pictures to my website sometime next week after I take it out of storage.
https://sites.google.com/view/mattat...aplesyrup/home