Homemade RO trial

[Andrew Franklin]

Stealing ideas from the excellent posts on this forum (don't know what I would do without it!) I built a RO for this season. I plan to use it at my lake property where my trees are. I brought home a few jugs of sap to test it out, and after much error and a little trial, I am pretty pleased, but have a few questions. I am going to pump from my storage tanks (275 gal totes) to a 55 gallon drum, then drip from that to a 5 gallon bucket with a bucket heater in it matching the rate of flow through the RO. From there, the warm RO concentrate will go into my Mason 2x4 evaporator. The warm sap will gravity feed into a well head pump, through a 5 micron filter, through an aquatech 8855 pump, ant then through 4 250 gpd LE membranes, with a needle valve on the concentrate line to restrict flow. It all worked pretty good, save the 5 micron filter leaking badly (hence the pan it is in - I think it needs a gasket on the top that didn't come with it?). My question - is the well pump necessary? My pressure didn't change much when I shut it off and the aquatech was sucking the sap through the filter, although the aquatech pump was noticeably working harder. Without the well pump my filter didn't leak. Is it ok to have the high pressure pump between the filter and the membranes? Or should I just fix the leak and go with the well pump and make things easier on the aquatech?

Picture here, but please note: it's ugly - put together in the few minutes between work and kids sports. I know that's a drinking water hose...just done to hook things up. I know that's a mountain of fittings on the well pump - the one I will use isn't a 1" pipe thread - I cobbled another pump I had in the garage. That said, all thoughts are welcome - thanks!15321

[mellondome]

Make sure you are pumping through the filter. Also having pressure before your ro pump will increases the pressure in the membrane, allowing it to work better.

[Bricklayer]

Your aquatech pump is pumping way less then your well pump. Basically your deadheading your well pump. You could throttle back your outlet from your well pump with a valve. The aquatech has a maximum inlet pressure of 60 psi. It's a diaphragm pump so you don't want to exceed that pressure. An oring on your prefilter will definitely stop the leaking.

[Clinkis]

The well pump is not necessary. Put your filter between your pump and membranes and suck directly out of your storage container. The Aquatec pumps will self prime and lift 6'-8'. When I used to have your style of RO I was drawing out of a 55 gallon drum with the RO mounted above it. You will need to get the proper gasket for the filter housing regardless.