Putting my RO to bed.

[Justin Turco]

My previous membrane used a liquid soap that was real easy. Now I have an XLE 4040.

What is the proper PH for washing?

Do you XLE guys also do an end of season acid wash and soak with citric acid?

And finally, what is the chemical for preserving the membrane and how much should I add to say...5 gallons of water in the wash tank?

Oh....and should I buy a gallon of antifreeze? I do keep the machine inside, but I hear it’s good for the rest of the ro to have it in the system.

[Justin Turco]

I found the answer to the question about preservative. Sodium meta-bisulfite. 1 TBL spoon in 10 gallons of water with 1 gallons of anti freeze. Same as my old membrane.

Still curious about the proper ph for washing and whether or not you guys are doing an acid soak?

[maple flats]

A soap wash is for organic compounds in or on the membrane, an acid wash is for mineral compounds that are in the membrane, you need both. First the Soap, then a good rinse followed by an acid wash. Post season, I suggest doing the acid wash for 2-3 weeks. Once the acid is filling the membrane canister, drain and rinse the wash tank.