6 ms·

I've used reverse osmosis unit for years. new unit is less than $100usd it paid itself in months. maintenance is cheap. my RO has kinda low efficiency. 4 units

I've used reverse osmosis unit for years. new unit is less than $100usd it paid itself in months. maintenance is cheap. my RO has kinda low efficiency. 4 units of water in, i get 1 unit of clean drinkable water. 3 units are 'waste' (don't believe what socmed says, it's not dirty). the waste water is used for laundry, aquarium and gardening. my fishes and vegs are thriving. to test purity, just plunge the ohm meter probes into a cup of ro water. if the resistence is in 1MOhm, it's pretty pure. mountain/mineral water bought from store is about 150kOhm. after drinking ro water for a while, store-bought water tastes slightly salty. my house pumps water from ground (well-pump). for a family of 6, i need 1m3 of water. that's about half hour of 500W pump. an ro unit (40W) runs about 3 hours for 5gal bottle. so give or take, 1/2kWH or about 15KW per month. that's about $1 or $2 for my water need per month. if i must buy raw water (such as living in an apartment), it's about $1 per m3, so about $30 per month; however, i get drinkable water too. ro units are portable. i saved $28/mo in water expense after moving from apartment. flashing back from memory, i used to lug around 3 5gal water-cooler bottle from stores to my apartment every 3 days (i had 3 bottles). it was not pleasant and wasted time (go to store, queue, lug heavy bottles back) ro unit has relay so you don't have to sit and wait for it to fill. it automatically cuts power to the pump when its internal clean-water-tank is full.

elliotec 10y ago
Wow, that's really interesting. Do you have other tricks you use for efficient homesteading? Using solar and whatnot?
chrissnell 10y ago
That's really cool. Do you face any regulatory issues for your pumping? Do you have to own water rights on your land to pump from the ground? Have you ever had your groundwater tested to ensure that there are no contaminants that might not be filtered by RO?
- dingleberry 10y ago
  water from well is okay for home use; however, for hotel, you need permit. i'm not overly concerned about contaminants because my water source is at the back of my house which has big trees, not some deserted mines. likewise, i never really question the safety of spring water bought from store. my crude experiment say that it's purer than spring water. that's should be sufficient. as far as i know, spring water is just that, water from spring, untreated.
- Amezarak 10y ago
  FWIW, it is typical for anyone who lives outside of a city to have well water. I would be shocked if there were any regulatory issues with doing so anywhere in the US, or any issue with water rights. There are millions of people doing it right now. I think hypothetically when the system is first installed it's supposed to be tested, but I don't put a lot of faith in that. Interestingly, in contrast to parent, it's pretty standard for the water to be totally unfiltered. Generally, you have an electric pump that cuts on any time the water pressure drops below a certain level to maintain it. Honestly I've no idea how much it costs me a month, but it's pretty nominal. My electric bill runs about $125/mo and most of that is the AC. (In case you were wondering, sewer is dealt with via a septic system, which still amazes me. All your wastewater drains into a ~1000 gallon tank buried in the ground. At the top of the tank are field lines, which distribute water and drain it over a wide area. Solids are rapidly broken down by bacteria in the tank and quickly dissolve. These systems can be maintenance-free for 25 years, though the septic industry recommends you pump them every several years to remove "sludge" that slowly accumulates at the bottom.)
  - dingleberry 10y ago
    to get water from ground, drill a hole about an inch diameter so long pipe can be inserted. if you can get good water within 9 meters, that's great because standard pump can suck up to 9 meter down. if you get salty, rusty, smelly colored water, drill deeper. 30m is pretty much max depth for home-use jet pump and normally you get clean water. you can get deeper too and use bigger hole too; however, that's when you need permit. industry and hotel often do because they need a lot of water very fast. water collected from pump can be stored in large tank above roof. then gravity plays it part delivering tank-water. there's a switch on the tank that cuts electricity to the pump when a buoy inside the tank float up to a certain level. so, my switch is simpler water-level-based, not pressure-based. from empty to full, my pump runs about 30 min. my pump is 1 horse power or about 750w. so for a month that would be 30 * 30/60 * 750w = 11.25 kwh. for disposals, my house get two lines. one for washing, bathing, etc and that goes to city sewer. another is for human waste that goes to house ground sewage tank. sewage tank is basically an unsealed empty space inside ground. bacteria decompose human waste and the water just get filtered by ground beneath. the tank gets full over time and sewer tank service can come and suck the sewage tank.
bahmboo 10y ago
You are ROing potable water from a well not from an ocean or sea. Costs and requirements much different.
- dingleberry 10y ago
  yeah, costs and requirements will be higher for saline water.
samcheng 10y ago
I was instructed (from professional chemists) to NOT drink 1 MOhm ( or other highly-purified) RO water. At that purity, particularly when hot, it will leach metals and other compounds from pipes, pots, cups, etc. Maybe it's worth dropping a little salt into the water after purification? I'm also surprised that you use the waste water on your aquarium. In my experience, fish are MUCH more sensitive to water quality than humans are. This is particularly true for corals in saltwater tanks. In fact, many aquarium stores sell RO-purified water for fish tanks!
- sevenless 10y ago
  I do not see why extremely pure water would leach metals any more than tapwater would. Chemically it should not matter. All species will reach equilibrium between the surface of the container and the liquid and if dilute they will not care about one another. That equilibrium will be reached faster if the temperature is higher. What is true is that you should not drink hot water from pipes because hot water does leach metals, tapwater or otherwise.
  - michaelcampbell 10y ago
    Was this not the issue in Flint, Michigan with the water leaching lead because it DIDN'T have something in it?
    - vessenes 10y ago
      No, the water there was more acidic than the prior water the system used, causing leaching.
      - michaelcampbell 10y ago
        I see; thanks.
  - ridgeguy 10y ago
    Very pure water is corrosive. I built a CVD lab that had aluminum deposition chambers plumbed into a DI water cooling system. The water was fed from a purifier that provided 18MΩ-cm water. The water corroded the aluminum chamber cooling passages, leaving aluminum hydroxide behind. This conversion of metallic aluminum to a gelatinous, clogging hydroxide was what alerted us to the problem. Feed pressure (regulated) was fine, but flow rates fell and chambers heated up. We had to wire brush all cooling channels, a total pain. We ran on tap water for a couple of weeks while we researched the issue, and had very little corrosion but had other issues (mineral deposits). Finally, we reverted to 18MΩ water and added ~10% volume of ethylene glycol (antifreeze, basically). Once we "degraded" the water purity with glycol, our corrosion problems stopped. It was very counterintuitive. Here's an industry source that has a little bit to say about the corrosive properties of pure water: http://www.lytron.com/Tools-and-Technical-Reference/Application-Notes/Deionized-Water http://www.lytron.com/Tools-and-Technical-Reference/Applicat.... Given the industrial importance of the problem, I'm sure there are in-depth chemistry explanations. Haven't pursued them.
y04nn 10y ago
How do yo check the resistivity, does it not depend of the distance? Is it 1MOhm/m?
- dingleberry 10y ago
  i standardized so that distance is not important. just use dry cup, plus and minus probe on tip opposite each other, dip probes to the metal end. it's not scientific, no replication, i did not even double blind myself and randomize. it's lazy, just for fun.
driverdan 10y ago
Why are you filtering well water? What's wrong with it unfiltered? Why did you buy water at a store when you lived in an apt instead of using city water?
- dingleberry 10y ago
  nothing wrong, when i was a kid, i often drink well water directly uncooked. i filter it because now i can and i have a son. well water are already filtered by nature. the deeper the well, the cleaner the water is. think spring water, which is rain water filtered by hundred-meter rock hill. water in apartment often smell funky and can't be trusted (management mix water from its own water-treatment with government water). i know for sure how nasty the apartment water because i often pour pure-strength (not grocery-bought) HCl or NaOH (wait for a day so they don't cancel out) down the drain when it's clogged in hope they dissolve matters. the pipe still sometimes gets clogged after harsh chemical treatments so lately i just use thick-liquid SLS (or use downy super in the USA, or any concentrated detergent) and pour hot water. it moves clog point down further the apartment pipe. slippery it is! i used to have my sink flooded within 10 seconds. now it's after 60 seconds, leaving plenty of time to do quick washings. that's history because now i live in a house.

elliotec 10y ago

Wow, that's really interesting. Do you have other tricks you use for efficient homesteading? Using solar and whatnot?

chrissnell 10y ago

That's really cool. Do you face any regulatory issues for your pumping? Do you have to own water rights on your land to pump from the ground? Have you ever had your groundwater tested to ensure that there are no contaminants that might not be filtered by RO?

dingleberry 10y ago
water from well is okay for home use; however, for hotel, you need permit. i'm not overly concerned about contaminants because my water source is at the back of my house which has big trees, not some deserted mines. likewise, i never really question the safety of spring water bought from store. my crude experiment say that it's purer than spring water. that's should be sufficient. as far as i know, spring water is just that, water from spring, untreated.
Amezarak 10y ago
FWIW, it is typical for anyone who lives outside of a city to have well water. I would be shocked if there were any regulatory issues with doing so anywhere in the US, or any issue with water rights. There are millions of people doing it right now. I think hypothetically when the system is first installed it's supposed to be tested, but I don't put a lot of faith in that. Interestingly, in contrast to parent, it's pretty standard for the water to be totally unfiltered. Generally, you have an electric pump that cuts on any time the water pressure drops below a certain level to maintain it. Honestly I've no idea how much it costs me a month, but it's pretty nominal. My electric bill runs about $125/mo and most of that is the AC. (In case you were wondering, sewer is dealt with via a septic system, which still amazes me. All your wastewater drains into a ~1000 gallon tank buried in the ground. At the top of the tank are field lines, which distribute water and drain it over a wide area. Solids are rapidly broken down by bacteria in the tank and quickly dissolve. These systems can be maintenance-free for 25 years, though the septic industry recommends you pump them every several years to remove "sludge" that slowly accumulates at the bottom.)
- dingleberry 10y ago
  to get water from ground, drill a hole about an inch diameter so long pipe can be inserted. if you can get good water within 9 meters, that's great because standard pump can suck up to 9 meter down. if you get salty, rusty, smelly colored water, drill deeper. 30m is pretty much max depth for home-use jet pump and normally you get clean water. you can get deeper too and use bigger hole too; however, that's when you need permit. industry and hotel often do because they need a lot of water very fast. water collected from pump can be stored in large tank above roof. then gravity plays it part delivering tank-water. there's a switch on the tank that cuts electricity to the pump when a buoy inside the tank float up to a certain level. so, my switch is simpler water-level-based, not pressure-based. from empty to full, my pump runs about 30 min. my pump is 1 horse power or about 750w. so for a month that would be 30 * 30/60 * 750w = 11.25 kwh. for disposals, my house get two lines. one for washing, bathing, etc and that goes to city sewer. another is for human waste that goes to house ground sewage tank. sewage tank is basically an unsealed empty space inside ground. bacteria decompose human waste and the water just get filtered by ground beneath. the tank gets full over time and sewer tank service can come and suck the sewage tank.

bahmboo 10y ago

You are ROing potable water from a well not from an ocean or sea. Costs and requirements much different.

dingleberry 10y ago
yeah, costs and requirements will be higher for saline water.

samcheng 10y ago

I was instructed (from professional chemists) to NOT drink 1 MOhm ( or other highly-purified) RO water. At that purity, particularly when hot, it will leach metals and other compounds from pipes, pots, cups, etc. Maybe it's worth dropping a little salt into the water after purification? I'm also surprised that you use the waste water on your aquarium. In my experience, fish are MUCH more sensitive to water quality than humans are. This is particularly true for corals in saltwater tanks. In fact, many aquarium stores sell RO-purified water for fish tanks!

sevenless 10y ago
I do not see why extremely pure water would leach metals any more than tapwater would. Chemically it should not matter. All species will reach equilibrium between the surface of the container and the liquid and if dilute they will not care about one another. That equilibrium will be reached faster if the temperature is higher. What is true is that you should not drink hot water from pipes because hot water does leach metals, tapwater or otherwise.
- michaelcampbell 10y ago
  Was this not the issue in Flint, Michigan with the water leaching lead because it DIDN'T have something in it?
  - vessenes 10y ago
    No, the water there was more acidic than the prior water the system used, causing leaching.
    - michaelcampbell 10y ago
      I see; thanks.
- ridgeguy 10y ago
  Very pure water is corrosive. I built a CVD lab that had aluminum deposition chambers plumbed into a DI water cooling system. The water was fed from a purifier that provided 18MΩ-cm water. The water corroded the aluminum chamber cooling passages, leaving aluminum hydroxide behind. This conversion of metallic aluminum to a gelatinous, clogging hydroxide was what alerted us to the problem. Feed pressure (regulated) was fine, but flow rates fell and chambers heated up. We had to wire brush all cooling channels, a total pain. We ran on tap water for a couple of weeks while we researched the issue, and had very little corrosion but had other issues (mineral deposits). Finally, we reverted to 18MΩ water and added ~10% volume of ethylene glycol (antifreeze, basically). Once we "degraded" the water purity with glycol, our corrosion problems stopped. It was very counterintuitive. Here's an industry source that has a little bit to say about the corrosive properties of pure water: http://www.lytron.com/Tools-and-Technical-Reference/Application-Notes/Deionized-Water http://www.lytron.com/Tools-and-Technical-Reference/Applicat.... Given the industrial importance of the problem, I'm sure there are in-depth chemistry explanations. Haven't pursued them.

y04nn 10y ago

How do yo check the resistivity, does it not depend of the distance? Is it 1MOhm/m?

dingleberry 10y ago
i standardized so that distance is not important. just use dry cup, plus and minus probe on tip opposite each other, dip probes to the metal end. it's not scientific, no replication, i did not even double blind myself and randomize. it's lazy, just for fun.

driverdan 10y ago

Why are you filtering well water? What's wrong with it unfiltered? Why did you buy water at a store when you lived in an apt instead of using city water?

dingleberry 10y ago
nothing wrong, when i was a kid, i often drink well water directly uncooked. i filter it because now i can and i have a son. well water are already filtered by nature. the deeper the well, the cleaner the water is. think spring water, which is rain water filtered by hundred-meter rock hill. water in apartment often smell funky and can't be trusted (management mix water from its own water-treatment with government water). i know for sure how nasty the apartment water because i often pour pure-strength (not grocery-bought) HCl or NaOH (wait for a day so they don't cancel out) down the drain when it's clogged in hope they dissolve matters. the pipe still sometimes gets clogged after harsh chemical treatments so lately i just use thick-liquid SLS (or use downy super in the USA, or any concentrated detergent) and pour hot water. it moves clog point down further the apartment pipe. slippery it is! i used to have my sink flooded within 10 seconds. now it's after 60 seconds, leaving plenty of time to do quick washings. that's history because now i live in a house.