RO water reading 50ppm, do I need to treat?

Water analysis, treatment, and mineral recipes for optimum taste and equipment health.
regalzack

#1: Post by regalzack »

Brand new Lelit Bianca, trying to do things right. I tested our RO water with the test strips provided by Clive Coffee and it's reading 50ppm, which seems to be within spec--however I realize that's probably not telling me everything regarding mineral content, etc.

I'm just wondering if I ought to be adding something(Rpavlis seems to be the go-to) to the water to be safe?
Thanks!


(I tried the search function, but I didn't find anything with RO that came back with 50ppm,so I figured I'd just ask.)

palica

#2: Post by palica »

Hello and welcome!

Did you try looking here: FAQs and Favorites

regalzack (original poster)

#3: Post by regalzack (original poster) »

Thanks, just looked through it, couldn't quite find what I'm looking for. It seems like most RO systems remove more ppm than mine, it seems like ~50ppm from a RO system is somewhat of a unique case.

Nate42

#4: Post by Nate42 »

What you get out of your RO is a function of the age/configuration of the filter and what is coming in. 50ppm does seem a bit high and could indicate that your filter is getting old or it could just mean you have quite hard water at the input. Also some systems deliberately mix in some untreated water for taste. It's important to know how your system is set up and what is "normal ". As to whether the water will scale that depends. You would need to test for hardness.

Nate42

#5: Post by Nate42 »

BTW I wouldn't hesitate to use this water or at least try it. If the coffee tastes good it's good. It's possible it would scale gradually over time but 50 ppm is low enough you aren't going to have any major issues.

regalzack (original poster)

#6: Post by regalzack (original poster) »

Thanks!

Yeah, I've been running it and although I'm still figuring my way around the machine I'm pulling pretty decent shots out of it. I'm guessing the filter is ~1 year old so that is definitely a possibility.

I'm assuming it wouldn't hurt anything to add some rpavlis mix (maybe like 1/2 dose) just to be safe?

Nunas
Supporter ♡

#7: Post by Nunas »

50 ppm is fine. There are lots of variables, depending on your setup. Blended output RO devices has already been mentioned. Another major factor is whether you have a whole house water softener (ion exchanger). If your RO is downstream of an ion exchanger, then the main element in your water will be sodium ions. You don't need to add anything "to be safe"; you may wish to experiment with additives for taste.

Nate42

#8: Post by Nate42 »

The bicarb in rpavlis water (potassium was recommended but sodium ie baking soda works in a pinch) is there for two reasons: to buffer the acid in coffee for flavor reasons, and to ensure your water is not acidic and thus doesn't corrode your boiler as too pure water could.

In your case, if you already have some bicarb in there adding more won't hurt anything but it might mute or dull your flavors. Do you have a way to measure your pH? If it's 7 or above I would leave it alone. If it's below 7 adding some extra bicarb might not be a bad idea. Chances are good you are fine as is.

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homeburrero
Team HB

#9: Post by homeburrero »

regalzack wrote:I tested our RO water with the test strips provided by Clive Coffee and it's reading 50ppm, which seems to be within spec--however I realize that's probably not telling me everything regarding mineral content, etc.
I agree with the advice from others above, but want to point out that your Hach test strip from Clive is giving you a very rough measure of hardness ions. You know it's more than 0 ppm and less than 120 ppm CaCO3 equivalent. It may or may not give you a little limescale deposits.

If your RO system has a remineralization cartridge, much of that 50 ppm reading is from that remin cartridge and you are probably about where you want to be. Down the road if you want to assure that your water is non-scaling you can use a more accurate and precise test kit and measure both the alkalinity (KH) and the total hardness (GH). The two of those together can tell you if you have non-scaling water.* A cheap and easy kit to do that would be the API fishcare GH & KH kit that's sold online and at aquarium supply stores.

One easy way to keep an eye on your RO performance would be to use a conductivity TDS meter. A cheap $20 unit would do the job. It gives you a rough indication about how much mineral is getting through your RO. If your membrane is fouled and not performing well you will see that TDS reading go up. A good RO unit should reduce the TDS reading from about 500 ppm at the tap to less than 30 ppm at the RO output, this is before it goes through the remin cartridge where it would pick up another 20 - 60 ppm of hardness minerals.

If you have a fancy RO unit with a blending valve to increase mineral in the output, it will probably come with a conductivity TDS meter and instructions about using it to adjust the blending valve.

* To use your alkalinity and hardness values to determine how much limescale your water might cause, the best reference out there is Jim Schulman's Insanely Long Water FAQ.
Pat
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DaveC

#10: Post by DaveC »

regalzack wrote:Thanks, just looked through it, couldn't quite find what I'm looking for. It seems like most RO systems remove more ppm than mine, it seems like ~50ppm from a RO system is somewhat of a unique case.
it depends on a few things, is the system pumped or not (if not at 500ppm get a pumped system), what is the % rejection rate of the membrane, incoming TDS, age of the membrane (especially if the water has a high chlorine concentration). Even down to do you use a water softener, RO systems love working with softened water and even if the TDS is high, no worries.

I read your membrane is a year old, the max is usually 2 years old, some membranes say change after a year. You may well need to change your membrane.