Reverse osmosis system recommendations

[PeteM]

A positive note is that the system is filtering the water down to 0 ppm total dissolved solids according to my meter.

Do you think if I remove the de-ionizing stage, it will produce at a better ratio, but with an increase in tds? I guess I could try it.

That’s amazing considering your starting point.. I can never get mine below 8 ppm. I think you should tinker and experiment while you are in the mode. Just remember you have to add back to the water, so anything below 20ppm you are still winning the game.

They are just not that efficient at this entry level, if you want a 1:1 ratio, you have to shop for the high efficiency RO systems.

 

[PeteM]

I was wondering how RO systems are legal in CO. Not a knock against you, I know living in the arid west they have laws that prohibit the use of rain barrels and evaporative coolers. I guess RO tech gets by for drinking water purposes. Maybe you can keep some of the discarded water in buckets and use it to flush toilets? Not sure what else you can do with it.

 

[My Green Pets]

The waste is awful. But then again, have you seen how popular those big fancy car washes are these days? I don't get it either.
I will save as much of the rejected water as I can, especially in summer when I'll (finally!) have an outdoor garden. Using it to flush the toilet is a good idea as this house still has old toilets that use huge amounts with every flush.

 

[PeteM]

The waste is awful. But then again, have you seen how popular those big fancy car washes are these days? I don't get it either.
I will save as much of the rejected water as I can, especially in summer when I'll (finally!) have an outdoor garden. Using it to flush the toilet is a good idea as this house still has old toilets that use huge amounts with every flush.

May want to look into how safe it is to use on edible plants. I’m not sure what else it’s pulling out that might be harmful. If it’s safe then it would open up more options. You can have fun experimenting watering lawns, shrubs and ornamentals. Cleaning outdoor items.

 

[gonewild]

You should calibrate your meter. 0 ppm is not likely.
Test your discharge water ppm it should be really high

 

[gonewild]

The lower the ppm in the filtered water means more gallons of waste water. There is no need to filter below 20 ppm.
Closing the supply water faucet will lower the pressure and raise the output ppm. And it will decrease the waste.

 

[Theodoreorchidking]

I dont have time to read all the suggestions and posts so I may be repeating things. I got the $80 or $100 RO thing that is from Amazon. It has like 3 cylinders. I just run it and use the water as it comes doing other house work in the mean time. I got the 75 gallon one. It has worked beautifully. I have never taken a true reading and honestly just went for it. However i have bloomed/in spike 2 rothschildianum, kovachii, phragmipedium hybrids, bulbophyllum, cattleya, nepenthes, butterworts, anthurium, angraecum sesquipedale, angraecum hybrids, brassavola, vanda. So in short it has done some of the most picky orchids you can get.

If you don't have time what I would do...
Get a bucket with how much water you need. It comes with and auto shut off valve. Run it for as much water you need. Heat this up to desired temp with a fish tank heater. It may also be the right temp

Best of luck

 

[Theodoreorchidking]

Also they suggested doing it in the bathroom tub just incase of an accident. I do it in my kitchen sink and water 300 plants a week

 

[Ray]

First of all, oh my GOSH does this thing waste water. I have filled two 5 gallon buckets with waste water and don't think I even have a gallon of RO yet.

I don’t know their setup, but typical permeate:brine ratios are in the 1:3 - 1:4 range. However, all of the specifications are at 65 psi/77F water at the membrane. Colder and/or lower pressure slows the flow through the membrane, decreasing the efficiency. It’s typically not worth the effort to boast the pressure or temperature unless they are extremely low, but the efficiency can be improved by using a slightly smaller restrictor on the flush water (brine) outlet. I‘d be happy to help with that, if you’re interested.

Interesting that the waste water reads at about 265 tds, still a bit better than the 400 straight from the tap

That simply means your meter is reading it differently. The brine now contains the dissolved solids rejected from the purified stuff, so has increased.

I have read that the higher the supply pressure, the more efficient the system. I have no idea what my water pressure is but I thought it was very high. Am I going to have to go buy a $15 pressure gauge that I'll never use again?

A positive note is that the system is filtering the water down to 0 ppm total dissolved solids according to my meter.

Do you think if I remove the de-ionizing stage, it will produce at a better ratio, but with an increase in tds? I guess I could try it.

If your tap water has decent pressure for a shower and faucets, there is no need to measure it.

You absolutely do not need the DI column, and it will get fouled and need replacement more quickly than the filters and membrane. Yes, the TDS will increase to probably no more than 20 ppm, which is fine for plants, and the water usage will also improve.

Understand the operation of RO systems: there is one raw water inlet and two outlets, permeate (purified) and brine (flush water). The brine outlet has a fixed flow restrictor that creates the back-pressure that pushes water through the membrane. That is fixed, so the flow through it is more-or-less constant at all temperatures and pressures. The flow through the pure water side is variable - anything that decreases the flow - low temperature, low pressure, or the DI cartridge - reduces the efficiency.

 

[Ray]

I was wondering how RO systems are legal in CO. Not a knock against you, I know living in the arid west they have laws that prohibit the use of rain barrels and evaporative coolers. I guess RO tech gets by for drinking water purposes. Maybe you can keep some of the discarded water in buckets and use it to flush toilets? Not sure what else you can do with it.

The waste is awful. But then again, have you seen how popular those big fancy car washes are these days? I don't get it either.
I will save as much of the rejected water as I can, especially in summer when I'll (finally!) have an outdoor garden. Using it to flush the toilet is a good idea as this house still has old toilets that use huge amounts with every flush..

Flush water can be used to irrigate less sensitive plants, can be dumped on the greenhouse floor for humidity, and can be returned the the well, if that’s your source. I used it to keep an artificial pond full outside my greenhouse - the wildlife loved it.

There is also a “zero waste“ kit available that uses a pump to inject the waste water into your household, hot water lines, downstream from your water heater.

You should calibrate your meter. 0 ppm is not likely.
Test your discharge water ppm it should be really high

0 is attainable with the DI cartridge, but you’re right, TDS meters are notoriously inaccurate.

The lower the ppm in the filtered water means more gallons of waste water. There is no need to filter below 20 ppm.
Closing the supply water faucet will lower the pressure and raise the output ppm. And it will decrease the waste.

As I explained above, the ratio of pure-to-waste is far less direct, and lowering the input flow kills the efficiency.

 

[My Green Pets]

Ray and everyone, thanks for the continued engagement on this topic.

My latest idea is to unscrew the shower head off an unused shower in the basement and try to connect the system to that. I will have to go searching for an adapter so that the garden hose-sized screw-on thingy will screw on to the shower head pipe, if such a thing exists.

Reasoning is, it's more convenient than messing with the washer faucet, can put the brine tube down the drain, and as an added bonus, i can adjust the temperature to be a little warmer to improve efficiency/speed of permeate production (thank you Ray for the vocabulary).

Please poke holes in my new plan if you see issues.

Attached are photos of the TDS meter in tap water, store-purchased distilled water, and the filtered water produced by the RO system last night (see file names for which is which).

 

[Ray]

Don't trust your TDS meter!

At close to zero, it is likely pretty good, but as the TDS increases, it's bound to be wrong.

Read this: Don't Trust Your TDS Meter

 

[gonewild]

Not likely that you have distilled water that is actually zero.
Ask your water company to tell you what TDS water they supply, compare that with your meter reading.

You can mix a measured amount of table salt with a measured amount of distilled water to make a calibration solution to test your meter.(I forget the amounts)

What is the ppm of the waste water? It should be significantly higher than the ta water.