Reverse Osmosis without a pressure tank?

tunaman

Due to lots and lots of household plants I have a large need for RO water. But it seems that all of them need a pressurized water storage tank. But I am going to be storing about 200 gallons of RO water enough that gravity feed will push out all of the water I need. How can I set this up so that the water is stored in a large non-pressurized tank?

AllanJ

You can run the reverse osmosis output into a non-pressurized tank with gravity feed to the greenhouse or garden. You would need a float switch to turn off the RO unit when the tank is full.

Some models of RO units don't actually turn off unless either the water inlet is shut off or the back pressure at the outlet builds up sufficiently (via a pressure tank), in which case you would need an electrically powered inlet valve as well as a float switch. Or let the RO unit run 24/7 and provide an overflow pipe from the storage tank to the garden or to a drain.

With a nonpressurized storage tank, (possibly germ laden) makeup air from the room or basement or outside is needed to occupy the tank when water is being drawn. The water would be non-potable unless chemical treatment was done later.

For those eavesdropping for whom gravity feed doesn't work, any number of additional and/or larger pressure tanks can be installed as needed.

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The disadvantages of crab apple trees. In summer, the apples are too sour to pick and eat. In winter the birds come and leave dropping all over the place.

joecaption

I must be missing something, why would anyone want to go to all the expence and maintaince of using one of these just to water plants?

Plants need minerals to grow, so why take them all out of the water?

Lightfoot

That was my first thought too Joe, but i guess the OP knows something i don't about growing plants. Perhaps the OP would be kind enough to tell us what benefits there are with RO. I'd really like to know, honestly. Maybe it's for a certain type plant, or something used in pharmaceutical use that requires it. But then again, he did say house plants. I'd still like to know.