ro vs distilled water?

[anewbie]

So i did a bit of searching before this posting because it seems a lot of results were confusing. Some talked about ro being purer (I thought distilled was purer) some talked about dstilling doesn't remove chlorine and a few other things.

The issue is that there are large very effiicent distiller out there and i was trying to decide if the trade off in more energy to produce dstilled water in exchange for virtually no waste water was a good trade off.

 

[MacZ]

Frankly, it's chemically so close you can call it the same and most distilled water on the market is actually RO. Just from industrial grade units, that can make RO water chemically identical to actual distilled water.

 

[Mike Wise]

If you want to reduce waste water in r/o production you should consider one of the high-pressure r/o units. These use a pump to force high-pressure water through the membrane. They are faster than standard r/o units and produce very little waste water. These also use less energy than a distiller.

 

[anewbie]

If you want to reduce waste water in r/o production you should consider one of the high-pressure r/o units. These use a pump to force high-pressure water through the membrane. They are faster than standard r/o units and produce very little waste water. These also use less energy than a distiller.

The current unit i have is 1:1 though refilling di canister is a royal pain - the ec without di is around 12 as my base water is harder than denver.

If there is an ro unit that is better than 1:1 that has high rejection rate can provide a pointer.

 

[Mike Wise]

I doubt than any r/o unit can do better than 1:1. You will need to decide for yourself if you are willing to accept the higher costs of operating a distillation unit or not. Personally 12 µS/cm is more than acceptable for any apisto.

 

[MacZ]

The best result I've seen was 1: 0.75, but that guy modded a unit himself beyond any warranty or safety concerns.

 

[anewbie]

The best result I've seen was 1: 0.75, but that guy modded a unit himself beyond any warranty or safety concerns.

Well there isn't much to warranty and safety would only be a problem with putting so much pressure on the canister they would burst - the ro system are pretty simple - i actually am bless with natural high pressure up to 120 psi out of the faucet though i have a pressure reducing valve to the ro unit to reduce to around 60 - the unit i have does have a pump though it isn't strictly required. The issue with high pressure is you can push extra sentiment through the membrane and if high enough pressure 'burst' or tear the membrane. Of course a lot depends on one tap water tds - as at least in usa it can range from very low (oregon, washington) sub tds 30 to very high well water over 400 tds. My sister used to live outside of milwaukee and i hated taking showers at her place the water was so hard. My current location has tds around 120 and my previous residence was below 100 so i've never actually lived anywhere with hardwater beyond visiting my sister.

I did read about some lab ro unit that was rated around 1:0.25 but i could never get fine details on it with regards to media consumption or rejection rate.

 

[MacZ]

and safety would only be a problem with putting so much pressure on the canister they would burst

I can ask for the exact pressure, but I think it was almost double the pressure the unit was cleared for. So... yes, possible bursting was an issue.

 

[Apistoguy52]

When I was using it more regularly, I ran my filmtec membrane at 200psi with a booster pump, and recirculated a good portion of the waste water to achieve a 2/1 ratio. I can’t imagine any quality membrane that wouldn’t be able to handle 125psi.

 

[dw1305]

Hi all,

My sister used to live outside of milwaukee and i hated taking showers at her place the water was so hard. My current location has tds around 120 and my previous residence was below 100 so i've never actually lived anywhere with hardwater beyond visiting my sister.

If you have a soft-water input to the RO filter you get a better yield ratio and the units last longer. Our tap water is about 600 microS (~ ppm TDS) and the DI units, <"in the labs."> at my former workplace, (I've just retired) used to get through a lot of consumables.

cheers Darrel

 

[anewbie]

Hi all,

If you have a soft-water input to the RO filter you get a better yield ratio and the units last longer. Our tap water is about 600 microS (~ ppm TDS) and the DI units, <"in the labs."> at my former workplace, (I've just retired) used to get through a lot of consumables.

cheers Darrel

My water is softer than that - around 140 tds; but not soft like some parts of the country. I have to replace consumable once a month (not the or membrane but filter and di risen). In truth the di risen doesn't last long and i refuse to replace it more than once a month. My guess is the ro memberan will last 6 months to 1 year but waiting to see.

 

[Mike Wise]

If you get an r/o unit with a back-flush option it should last much longer than a year.

 

[RobynMc]

So i did a bit of searching before this posting because it seems a lot of results were confusing. Some talked about ro being purer (I thought distilled was purer) some talked about dstilling doesn't remove chlorine and a few other things.

The issue is that there are large very effiicent distiller out there and i was trying to decide if the trade off in more energy to produce dstilled water in exchange for virtually no waste water was a good trade off.

 

[RobynMc]

I have done lots of research on water because I have a well with too much sodium and boron—so I have to use a mix of bottled waters for my aquariums. RO and DI water purity depends on the efficiency of the system. I looked into a home distillation system for my home and discovered they use a LOT of electricity. So no go for me on that. An RO system with an additional electric pump is more efficient at removing water pollutants and less wasted water. I have a system for drinking as well as a remineralizer and an alkalizer. Because of my particular water chemistry, the RO system dropped the ph down into the 5.0 ranges, which is not great for drinking. Still cannot use my treated water on plants and aquarium fish because boron requires more steps to remove (too much is death to plants) and would be very expensive. Both DI and RO water do need remineralization for use with fish tanks and depending on your particular situation, many even need remineralization for drinking. I don’t know who told that that distillation does not remove chlorine, but I believe that to be untrue. Many people confuse boiling water with distillation, which are not the same process at all. Boiling water and letting it aerate may remove chlorine and bacteria, but not necessarily remove chloramines or any other harmful substances like heavy metals and other chemicals. You can check with your local water treatment municipalities to see what is used. Aeration does not remove chloramines. Water can be complicated, so good to test with liquid test kits and also check the gh and kh because that info is needed to provide good water for fish. KH too low or nonexistent in water can be unstable and fish and plants do need minerals in their water, as well as humans. I have found some of the RO and carbon treated water dispensers (often at grocery stores) can be a lot less expensive, but I still test the water. I found one system that had a filter issue and the water had high nitrates in it—so had to dump it. I contacted the company because clearly, they had not been doing regular maintenance or else something went awry. I test all new source water going into my aquariums and also check ph on “trusted” bottler sources because that can vary from batch to batch. I keep distilled on-hand to mix it with before adding to tanks, if the ph on the purified or spring water runs a bit high, because I keep some fish who prefer lower ph.

 

[anewbie]

If you get an r/o unit with a back-flush option it should last much longer than a year.

The unit i have does have the black flush logic. The issue is the raw amount of water i'm using - which is approx 4500 gallons a month (or 9000 going through the system which is 1:1). I'm not sure how much water you use or how many aquariums you have - if i had more ro water iwould consider making my 500 and 600 softer but as it is i'm kind of at my limit. I could use less water if i did smaller water changes but in general for the aquariums 40 gallons or less i do 50% once a week and for those larger i do a flat 40 gallons.