Well Water and RODI Unit

[jo-d]

I am considering getting a RODI unit, however, I am on well water. What is the standard waste water that it takes to make 1 gallon of RODI water from your personal experiences? Does anyone currently have a RODI and on well water. I have had great success in using the water units outside of grocery stores. I know a lot of ppl haven't. But I guess being in a small town, we do not have that many ppl using it so the filters stay cleaner longer. Besides, it's hard to beat .35 a gallon:up:. I usually haul 20 gallons at a time.

My other thought was to purchase RODI from someone locally.


I have a 1 year old 55 gallon mixed reef. Hoping to upgrade to a larger tank.

 

[johnqx4]

The general thought is 4 to 1. 4 gallons wasted to 1 good. I have heard 50% plus or minus over the years. however if it is more than 4 to 1 your membrane needs to be replaced. with a 55, you probably shouldn't worry much. even if you dump a couple hundred gallons a month... that is not that much. if you catch it for plants or some such other, that is even better. I used to suggest what you could do with the waste water, but I got tired of being hammered. Just remember the "waste" water has been filtered twice and is way cleaner than what comes out of your faucet. It makes great coffee and tea!

 

[jennm]

RO wastes between 3 and 4 gallons, per one gallon of filtered water when the unit is operating at peak efficiency, which is water temp 77F and 65 PSI. You can use that brine (waste water) to water plants, do laundry, etc., it doesn't have to go down the drain.

If your temp and pressure are different the ratios will be different.

Jenn

 

[johnqx4]

Jenn,

Your answer (as usual) was spot on (albeit) with one slight exception. To refer to the "waste water" as brine is incorrect. Brine would indicate that it is salt water which is not the case. In most 3 stage rodi units (as mine is) the fresh water passes through a white sediment filter, then a carbon filter before it ever hits the membrane. What passes through the membrane is the cream (so to speak) of the crop. The water that didn't make it is still much cleaner than what would have come out of the faucet and it is fresh, not brine.

Most people don't care about the waste water so this response was probably a waste of time. But that water is clean and useful if one cares. And it does make great coffee:yay:

Just my $.02 worth

 

[shrimpy brains]

I have had two houses with RO/DI units and well water. Never had an issue! CIty water just cost more as you pay for the amount you use, plus sewage(most places)

 

[jennm]

johnqx4;1096757 wrote: Jenn,

Your answer (as usual) was spot on (albeit) with one slight exception. To refer to the "waste water" as brine is incorrect.

Well, my boss, who is a WQA Certified Water Specialist, level V, refers to it as brine. I think I'd take his word for it.

Google "reverse osmosis brine". I think you will find MANY references to it.

So, respectfully, I am not incorrect here.

Jenn

 

[jennm]

bonez;1096823 wrote: I'm also on a well with an RODI unit the one thing you will need with the unit is a booster pump to keep the pressure up with out it you will waste a lot more water.

That's correct. The longer it runs, the more water it wastes. If it takes 1 hour with the booster pump to generate a gallon of RO/DI water, it wastes a lot less than if it takes 3 hours due to low pressure.

Jenn

 

[johnqx4]

JennM;1096785 wrote: Well, my boss, who is a WQA Certified Water Specialist, level V, refers to it as brine. I think I'd take his word for it.

Google "reverse osmosis brine". I think you will find MANY references to it.

So, respectfully, I am not incorrect here.

Jenn

Well, your boss might be brilliant. Webster's dictionary "The Source for America" since 1828 has a different opinion (oh, and you can google it as well)


1brineplay
noun ˈbrīn
Popularity: Bottom 50% of words
Simple Definition of brine
: a mixture of salty water used especially to preserve or add flavor to food
: the salty water of the ocean
Source: Merriam-Webster's Learner's Dictionary
Examples: brine in a sentence
Full Definition of brine
1
a : water saturated or strongly impregnated with common salt
b : a strong saline solution (as of calcium chloride)
2
: the water of a sea or salt lake

 

[jennm]

I'm well aware of the other definitions of the word.

For what it's worth, salt is one of the things that the reverse osmosis process removes from water.

Believe me, don't believe me, I won't lose sleep. I know I'm correct here.

Jenn

 

[jo-d]

Awesome! that helps out. Thanks for all of the info.

 

[jo-d]

I guess I could use the waste water for the pool or animal water buckets during the spring, summer and fall. We do live on a farm so we are always needing water for something. Maybe investing into one of the large IBC tanks for waste water. It would make it easy to move with the tractor. hmmmmm. now you got me thinking.

 

[walterp1982]

I'm on well water. Sometimes we bleach the well to keep anything from growing in there. Be sure not to RODI during that period if you do it, it will deplete your di resin quickly.

Other than that, well water is sediment and mineral heavy. I put a 20 micron sediment canister on the whole house, then an extra 5 micro sediment canister just before my RODI, which uses 1 micron canisters.

This GREATLY reduces 1 micron filter clogging, as before it was catching everything

Sent from my SM-G935F using Tapatalk

 

[jennm]

The chlorine should never get as far as the DI resin, because chlorine ruins the membrane. The carbon blocks adsorb the chlorine, so after chlorination, change the carbom blocks more often.

Sent from my SM-J320P using Tapatalk

 

[jo-d]

The extra filtration is exactly what I was thinking as well. It would help to extend the life of the rodi filters. I do know all about the sediment. Lol

 

[jennm]

Sediment filters are cheap. Like $3 cheap, or less if you buy quantity. Change them as often as needed and that helps prolong the life of the other elements. Same with carbon cartridges. Also cheap. Keep those first 2 stages clean and the membrane will serve you well for a long, long time, as well as the DI resin.

Replacing the cheap elements often means replacing the more expensive elements less often. It's a no-brainer.

And if you have a lot of sediment, you can run several sediment filters in succession. Start with a larger micron cartridge, going down to smaller - like 20 or 10 down to 5 or even 1.

Jenn