Reverse Osmosis

The manufacture of my system is no longer around. Sam's Club here has a system they sell and have been selling for close to 8 years now. Mine discharges to a 55-gallon plastic drum. A sump pump from Lowe's pumps the RO water out (the first one I bought back in 2000 just died twoo weeks ago). Attached to a hose with a spray head I use it to water the greenhouse.

 

Alexis, it's not necessarily that you need a big system, but you will need some larger storage for the water that you want to be ready to go. I think I've got either a 75 or 100 GPD but used to have a 50 GPD and that was fine. I have 20 gallons of pressurized tank that I store it in, but any plastic drum would be fine. The pressurized tanks that I have mainly are to get the water into my sprayer without having to use a pump.

Most people who have RO systems put the drums or tanks under their benches so as not take up too much space and to keep the water at g.h. temp.

I bought my 5 stage system over the net at www.waterfiltersonline.com They've got quite a few to choose from.

 

The limiting factor on how much RO a system can produce in one day is the rate of the membrane. Lots of home systems have a 100 gallons per day rating, so a couple of membranes in parallel would work great, I'd think. For water storage tanks, go to a local car wash and get a couple of the old concentrate drums and rinse them out with vinegar, then rinse with baking soda for good measure. They're great for water storage, and they're generally pretty inexpensive. And, like Marni said, get a shallow well pump. The pressure is much better; you won't regret it.

 

My only problem with RO systems is the amount of water that is wasted in the process. I found that for every gallon of RO I got I ended up with 5 gallons of water that was not usable on my plants. Now, if I had a way to return this to my well then that would be great. If I had a place to store it like a pond and use it for watering landscape that would be good too. But, I have neither and since I have a well I really didn't like the idea. So, I decided to catch rainwater instead and it seems to work well. I'm currently storing about 600 gallons in a series of tanks. I will eventually get the all plumbed together but haven't yet. I have a well pump and tank to provide the pressure and my intent is to switch over to this completely. If I had a 1000 gallon tank I could fill it easily in one rainstorm. I have tested the water and it is almost identical to RO water but with a slight stain mostly from leaves.

 

Harry, we are metered here, so we pay for our water use. I have the excess going into my evaporative cooler. It makes me feel less guilty about the run-off. I'm sure it somewhat decreases the lifespan of the cooler pads, but I think it's worth it.

 

You can also return the waste water to your hot water heater, resulting in less waste.

 

There are many ways to skin a cat.

The tank idea for water demand is number 1. The system can create water while you're not using it, so you simply store enough to use.

Choking down the flush water will reduce the membrane life, even at a 2:1 ratio. Finding an alternate use for that water is a better idea. I fill a pond for the local wildlife; the overflow makes its way back into the aquifer. The hot water system is another great idea, although it does take a pump.

If your demand is really high, you can go with a GE Merlin system that is rated up to 700 gpd, but they are quite pricey and the replacement parts follow that.

 

is it easy to store a tank under the bench without getting watering water in it? where do i find low height tanks like that? Does a well pump need to be manually powered on every time it's used or can be left turned on? Can the pump be exposed to watering water or needs to be sheltered? sorry lots of questions!

 

All are of the above is good advice and I considered it all before going for rain water. I have an expandable system that gets replenished whenever it rains. The water seems to be almost as good as RO water and it's free. To get a cleaner supply I'm adding gutters to the greenhouse where it runs off plastic and not shingles. I still have a ways to go to get it totally operational but I think it's going to do well.

I did some side by side test with the water on identical plants from the same vendor. I watered one with RO and one with rain water. There seemed to be no difference in the health of the plant over a period of 6 months. While this wasn't a scientific test it did give me enough confidence that the water is good. Certainly better than my well water although it was not all that bad.

 

Unless you live in a fairly industrialized area, or one with lots of automobile use, rainwater is just about as pure as it gets.

Armando, you'll want a pump with a bladder tank and pressure switch, or you're going to have to manually turn it on before watering, and off afterward. Otherwise, you'll burn it out in no time.

 

Two observations - #1 Marni has Hetch-Hetchy water which is around 50-100ppm out of the tap. I'm assuming this contributes to her ability to allow the membranes as long as they do. #2 California has "seasonal" rain pattern which doesn't allow us to count on rain water collection. I can and do collect several hundred gallons of water, but that only lasts me a couple weeks after the rains stop (think march/april). We don't get more rain for 9 months. If you live in a place (aka not the southwest), then rainwater collection is a great way to go.

 

50-100 ppm of what? Chlorine? Since Alexis lives in Florida where there normally is no scarcity of rain I was thinking of that when mentioning a catchment system. Even so, a catchment system is only restricted by it's size since even a small house during a heavy rain can exceed most any size tank.

 

Well we all use a catchment system. Some catch their own and some don't.

I once had a pipe break in the greenhouse and it put about 1 foot of water over an area about 50'x100'. That's about 5000 cubic feet of water. That's about 40,000 gallons so yep I can imagine it. That all came out of my well overnight.