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Re: Distilled water
Posted: Mon Aug 22, 2016 6:34 pm
by still_stirrin
dk,
Hard water will destroy the osmotic membrane. So, in order to use a RO filter, you need to first soften it (eliminate the total hardness). Unless you have a whole house water softener, adding a RO machine would be a waste of money.
But then again, calcium build up in your plumbing, including the water heater will cause premature failure of the household plumbing. So, it would be wise to put in a softener in the house or you'll be paying for it sooner or later by replacement of the plumbing.
Do you get calcium build up on your glasses now? Do you find that you have a hard time getting a good lather up in the shower? Hard water problems.
ss
Re: Distilled water
Posted: Mon Aug 22, 2016 6:52 pm
by still_stirrin
Wiski,
Pumping a little more pressure into the bladder in the RO water tank will help it push the water out better. On my Whirlpool RO system, the air pressure in the tank when it is empty of water should be 5 to 7 psi. But the system requires at least 50 psi water source pressure to work properly. If your supply pressure is 50 psi, or lower, that would definitely be a problem to push water into the ice maker.
Another thing that might help your plumbing system would be to add another pressure tank. That would double the water capacity before running out of pressure. You can buy another tank to parallel the original at the big box stores.
My supply pressure is about 68 psi, so I have plenty of pressure to drive the RO filter and still push the water to the ice maker. I hope you can get yours to work too. Clear ice cubes look "sexy" when you pour your homemade whiskey over them.
ss
Re: Distilled water
Posted: Tue Aug 23, 2016 1:54 am
by der wo
still_stirrin wrote:Hard water will destroy the osmotic membrane. So, in order to use a RO filter, you need to first soften it (eliminate the total hardness). Unless you have a whole house water softener, adding a RO machine would be a waste of money.
Hm I don't know. The hard water is the reason, why my girlfriend bought the RO machine. And why so many aquarists use them. And it works good without replacing the membrane for years. Our machine has a flushing function, a handle which switches to either flushing the machine or producing RO water. Perhaps because of that the membrane works so long.
Re: Distilled water
Posted: Tue Aug 23, 2016 4:25 am
by still_stirrin
Perhaps your system is different than mine der wo.
This is the specifications from my Whirlpool RO system:
Supply water pressure limits . . . . . . . . . . . . . . . . . . . . . 40-100 psi (280-689 kPa)
Supply water temperature limits . . . . . . . . . . . . . . . . . . . 40-100 °F (4.5-37.7°C)
Maximum total dissolved solids (TDS) . . . . . . . . . . . . . . . . 2000 ppm
Maximum water hardness @ 6.9 pH . . . . . . . . . . . . . . . . . 10 gpg (grains/gallon)
Maximum iron, manganese, hydrogen sulfide . . . . . . . . . . 0
Chlorine in water supply (max) . . . . . . . . . . . . . . . . . . . 2.0 ppm
Supply water pH limits (pH) . . . . . . . . . . . . . . . . . . . . . . 4-10
Product (quality) water, 24 hours . . . . . . . . . . . . . . . . . . 18.4 gal. (69.6 liters)
Percent rejection of TDS, minimum (new membrane) . . . . 68.5 %
Automatic shutoff control . . . . . . . . . . . . . . . . . . . . . . . yes
Efficiency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12.2 %
Recovery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22.9 %
So you see that there is a limit to the total hardness the system can tolerate, at least for the Whirlpool model. Your aquarium RO filter may be made from different materials and have a different limit. Or perhaps the water isn't as hard as you estimate. I know that water in Bavaria is quite soft. In the north, it may be much harder than the south. You would better know that than I.
ss
Re: Distilled water
Posted: Tue Aug 23, 2016 5:03 am
by der wo
I think it's a different system. And mine is much smaller (around 30l per 24h). I don't see a limit for hardiness on my system. But it's written, that high hardiness needs more often flushing the membrane.
We have 20°dH, what means 3.5mmol calcium carb per liter. I don't know how to calculate it in your measurements. 16°dH is the average in Germany, 20°dH is high but not the maximum. After RO filtering °dH is 0-1 °dH.
Re: Distilled water
Posted: Thu Aug 25, 2016 6:16 pm
by wtfdskin
How much RO water would you like. I can hook ya up.

Re: Distilled water
Posted: Sat Sep 03, 2016 1:54 pm
by cob
still_stirrin wrote:As for the costs, there is the system cost. Plus, as you use the system, the pre and post filters have to be periodically replaced. I replace them every 6-8 months, but again, I drink a lot of water (estimate a gallon per day at least, plus ice cubes). So, there is a recurring cost there. But the benefits of drinking water are invaluable and the machine is more economical than buying bottled water to drink as a staple. ss
there is a hidden cost for an RO system especially if you are on a well.
most RO systems are set to a 13/1 use ratio. meaning 14 gallons of supply
water flows through the system and you get to keep 1 gallon of finished water.
the rest is down the drain as flush water. on a well this could lead to
increased pump cycles depending on how much RO you use.
even municipal water costs $0.ox per gallon.
Re: Distilled water
Posted: Sat Sep 03, 2016 5:13 pm
by wtfdskin
cob wrote:still_stirrin wrote:As for the costs, there is the system cost. Plus, as you use the system, the pre and post filters have to be periodically replaced. I replace them every 6-8 months, but again, I drink a lot of water (estimate a gallon per day at least, plus ice cubes). So, there is a recurring cost there. But the benefits of drinking water are invaluable and the machine is more economical than buying bottled water to drink as a staple. ss
there is a hidden cost for an RO system especially if you are on a well.
most RO systems are set to a 13/1 use ratio. meaning 14 gallons of supply
water flows through the system and you get to keep 1 gallon of finished water.
the rest is down the drain as flush water. on a well this could lead to
increased pump cycles depending on how much RO you use.
even municipal water costs $0.ox per gallon.
The are definitely not the most efficient systems. The unit I pictured above rejects 77-80% of the feed water. We feed 800 gpm. Lol. Adding another unit and 3 more microfilters for pretreatment next year.
I don't care to drink ro water. Its too pure. All minerals are stripped along with the flavor. But if your well water is suspect they are great.