TDS Meters - Useful or Just a Gimmick?

[easysurfer]

Had an issue with my Brita water pitcher and filter the other day. So, starting looking at a different brand.

Ran across a brand called Zero Water where the pitcher came with a meter that measures the Total Dissolved Solids (TDS). Their filter is 5 stages and filters out away any dissolved solids down to zero (thus their name).

Next thing, I'm looking at Youtube videos (you know, if something is on Youtube, then it has to be true ) where people are using these meters to test the TDS of their tap water vs bottled water.

On guy talked about his Zero Water filter pitcher he takes along with his RV as the water in the RV park or from his RV's sink contains more TDS.

Of course, I had to go ahead and order a TDS meter. As now, I'm curious as to what the tap water at my place is and how well my Brita pitcher filters things out. I do see where a meter could come in handy when at a hotel as I've been guilty of just filling a water bottle with the tap water from the sink. Maybe should have just got bottled or measured first.

 

[Jerry1]

Maybe should have just got bottled or measured first.

Maybe you should just get a filter you trust. I don’t know if that’s Zero or Britta or some other brand but I’d look into that. The one we use on our refrigerator is NSF 42 and 53 certified. The cheap filters are just NSF 42. NSF 53 addresses things like lead. NSF 42 is more related to taste by removing orders and I think chlorine. There are probably even better filters out there, but not sure about the portable ones like Britta. Personally, I have a belief the TDS is a bit of a marketing thing but I have not looked into it enough since we drink from the filter in my fridge, which I trust. Maybe not as good as something like reverse osmosis, but as good as I’m willing to go.

 

[Gumby]

As far as I know, there is no TDS exposure limit. It's just a measure of how much soluble stuff is in the water along with the H2O. The dissolved solids could all be harmless salts, or they could be arsenic. The TDS meter won't tell you; it just measures conductivity. Higher TDS equals higher conductivity. I think you'd need to use chromatography to identify precisely what is in the water and whether it is dangerous or not.

 

[ERD50]

As far as I know, there is no TDS exposure limit. It's just a measure of how much soluble stuff is in the water along with the H2O. The dissolved solids could all be harmless salts, or they could be arsenic. The TDS meter won't tell you; it just measures conductivity. Higher TDS equals higher conductivity. I think you'd need to use chromatography to identify precisely what is in the water and whether it is dangerous or not.

Correct.

I bought a cheap ($12~$15?) TDS meter a few years ago from Amazon. Mainly to verify my Reverse Osmosis unit.

I'm on a well with high mineral content. The TDS reading before and after the water softener is essentially the same - the sodium replaces the minerals. So it can't tell the difference, and TDS is truly the same. But the RO takes out ~ 95% or so, as it should.

I'm not sure a Britta type carbon filter will take out much in the way of minerals, as others say, definitely chlorine, maybe lead, not sure about other stuff.

-ERD50

 

[GrayHare]

We get lots of essential minerals via water, so taking all those good minerals out like Zero claims to do, is something I prefer to avoid.

 

[easysurfer]

As far as I know, there is no TDS exposure limit. It's just a measure of how much soluble stuff is in the water along with the H2O. The dissolved solids could all be harmless salts, or they could be arsenic. The TDS meter won't tell you; it just measures conductivity. Higher TDS equals higher conductivity. I think you'd need to use chromatography to identify precisely what is in the water and whether it is dangerous or not.

Yes. That's why I'm thinking probably more a gimmick than anything.

 

[Sunset]

We currently use a Brita.
My concern about it besides the only 50% reduction in lead that it supposedly does, is that I wonder how the filter stops the water from leaking between the jug insert and where the filter inserts.

This is making think I should get a filter that attaches to my tap so the water doesn't leak around.

Am I wrong ??

 

[Sunset]

We get lots of essential minerals via water, so taking all those good minerals out like Zero claims to do, is something I prefer to avoid.

I for one , want the flouride in my water, but Zero claims to remove 97% of it.
I had terrible teeth as a child, which corrected itself (stopped getting cavities) once we moved to where there was fluoride in the water.

 

[CardsFan]

If you are on Municipal water, lower TDS=BS (There are a few exceptions to this, but more than 99% of areas apply). If you are on a well, it all depends.

We Americans are very fortunate that we can turn on the water almost anywhere without any concern about bacteria, diseases, etc. In my former life, clients from China would refuse to drink tap water. Only bottled. They know they have to do that at home, and accept it as the norm. I understand that position (I almost said paradigm, but I don't work anymore so I don't have to)

Even Europeans are leery of tap water.

 

[easysurfer]

We currently use a Brita.
My concern about it besides the only 50% reduction in lead that it supposedly does, is that I wonder how the filter stops the water from leaking between the jug insert and where the filter inserts.

This is making think I should get a filter that attaches to my tap so the water doesn't leak around.

Am I wrong ??

My Brita pitcher that started acting up is how I got to the TDS road on the first place. I have an older Brita pitcher and use Brita compatible filters. But what happens is the filter, with a fill pitcher would float, thus mixing the filtered and non-filtered water.

At first I thought issue was the non-Brita brand filters. But after "googling" saw that this is a common problem where the newer Brita filters don't completely fit the older pitchers.

My next pitcher/filter combo is going to have a filter that screws in place instead of just dropping in place like with Brita.

 

[RobbieB]

The muni water here is very good. I use 2 carbon block filters, 1 whole house and 1 under kitchen sink to remove chlorine odor.

Sweet!

 

[OldShooter]

Turn on water, put in the coffee pot, make coffee. Done. On the scale of life's perils, US tap water doesn't move the alarm needle.

 

[ncbill]

If one's water has lead or arsenic (the latter is surprisingly common in groundwater) problems one should pony up for a whole-house solution & not rely on the tiny filters in pitchers.

 

[CRLLS]

Correct.

I bought a cheap ($12~$15?) TDS meter a few years ago from Amazon. Mainly to verify my Reverse Osmosis unit.

I'm on a well with high mineral content. The TDS reading before and after the water softener is essentially the same - the sodium replaces the minerals. So it can't tell the difference, and TDS is truly the same. But the RO takes out ~ 95% or so, as it should.

I'm not sure a Britta type carbon filter will take out much in the way of minerals, as others say, definitely chlorine, maybe lead, not sure about other stuff.

-ERD50

^ +1

We are on a well and do the same. We soften all inside water. All drinking water and ice comes from the RO system. Our TDS meter reads about 950ppm before and after the RO system. I guess the Softener is working properly. (I test that occasionally too). I used the TDS meter on the drinking water occasionally to confirm that the RO filter is still functioning as it should.

I wouldn't worry about any of this if I has municipal water, with the exception of Flint, MI of course

 

[NoMoreJob]

^ +1

We are on a well and do the same. We soften all inside water. All drinking water and ice comes from the RO system. Our TDS meter reads about 950ppm before and after the RO system. I guess the Softener is working properly. (I test that occasionally too). I used the TDS meter on the drinking water occasionally to confirm that the RO filter is still functioning as it should.

I wouldn't worry about any of this if I has municipal water, with the exception of Flint, MI of course

Wow....are you sure you have your numbers right? Less than 60ppm is typically considered 'soft' and anything over 180 is EXTREMELY hard. A reading of 950ppm would indicate that neither your softener nor your RO are doing their job, or you have a defective meter.

If your water is indeed 950 before your RO you should be down to 50 or less after your RO if it's working properly.

 

[samclem]

Yes. That's why I'm thinking probably more a gimmick than anything.

I think you are right. TDS isn't a health or even a taste problem in itself. I think most people find that drinking water with a moderate amount of "hardness" tastes better than water with none (distilled, etc), and many of these minerals are beneficial.

The ZeroWater filter is a bit of gimmick, too. or, maybe "clever". The cutaway and explanation of components is here: https://www.zerowater.com/why-zerowater.php#whyZWSection_1

After the normal carbon and other filter elements, it has the special filter media that lowers the TDS: ion exchange resin beads. These are almost surely exactly the same beads that are in a water softener, and which remove hardness (calcium, magnesium carbonate, etc) in the water. The "hardness" ions bind to these plastic beads. But in a water softener, the beads are periodically purged of the hardness ions by a salt rinse, and sodium chloride temporarily takes the place of the hardness ions. When the next filtering process occurs, the resin again traps the hardness molecules, and the sodium chloride gets bumped off and into the drinking water (where it can be removed, if desired, by reverse osmosis).

In the ZeroWater filter, the filter cartridge (with the resin beads) gets thrown away rather than rinsing and re-using the beads. It's pretty wasteful from this perspective. If you've got water in the typical hardness range (less than 200 PPM TDS), the cartridge only lasts for 25-40 gallons. With the water from my well (TDS of over 800, and tastes just fine and entirely safe to drink according to the lab tests I've had run), I'd have to replace the ZeroWater fiilter every 4 gallons. The filters are $15 each. Ridiculous.

We could drink the well water, but as it is I soften the water to the inside fixtures (removing the hardness ions but adding sodium in the process), then the drinking water/icemaker water goes to the filter set (sediment, carbon) then apply RO to remove the sodium, then some UV light to kill any nasties. It's probably overkill, but recurring costs are low and I paid about $1200 for the whole system about 15 years ago. Going with the ZeroWater system, we would have spent $30,000 in filters by now, and generated several thousand pounds of unrecyclable solid waste (filters).

 

[Jerry1]

with the exception of Flint, MI of course

Flint was a special case, but since then, many communities are testing and finding old lead service pipes. Lead is not likely in the water leaving the water treatment plant, but that doesn't mean it's not there by the time it gets to your faucet. I tested for lead the minute I took possession of my current house (circa 1956) and found none, but it still seems prudent to use a filter that will handle lead and other metals.

FWIW, even in Flint, the water leaving the treatment facility was lead free and okay to drink, but they did not treat the water properly and there was a chemical reaction with the city's old lead pipes that caused that lead to leach into the water and affect most, if not all of the city's water at the tap.

 

[easysurfer]

....

In the ZeroWater filter, the filter cartridge (with the resin beads) gets thrown away rather than rinsing and re-using the beads. It's pretty wasteful from this perspective. If you've got water in the typical hardness range (less than 200 PPM TDS), the cartridge only lasts for 25-40 gallons. With the water from my well (TDS of over 800, and tastes just fine and entirely safe to drink according to the lab tests I've had run), I'd have to replace the ZeroWater fiilter every 4 gallons. The filters are $15 each. Ridiculous.

....

I already ruled out ZeroWater for my next pitcher/filter because of cost alone.

 

[samclem]

Our TDS meter reads about 950ppm before and after the RO system.

This is a problem. It would be normal for your TDS to read the same before and after the water softener, but it should be a lot lower after the RO.

If your water is indeed 950 before your RO you should be down to 50 or less after your RO if it's working properly.

I agree it should be a pretty low, but maybe not that low. I just measured my water: 1200 PPM after the water softener, 110 PPM at the drinking water tap. Directly after the RO membrane when it is actively running, the reading is 60 PPM. My RO membrane is advertised as providing a 95% reduction in TDS, which matches my measurements pretty closely (60/1200 = 5% remaining, so 95% reduction).

"TDS creep" is the reason the water we actually drink is 110 PPM and not 60 PPM. Some TDS creep is normal in RO systems that store water. There are ways to reduce it.

 

[CRLLS]

Wow....are you sure you have your numbers right? Less than 60ppm is typically considered 'soft' and anything over 180 is EXTREMELY hard. A reading of 950ppm would indicate that neither your softener nor your RO are doing their job, or you have a defective meter.

If your water is indeed 950 before your RO you should be down to 50 or less after your RO if it's working properly.

This is a problem. It would be normal for your TDS to read the same before and after the water softener, but it should be a lot lower after the RO.

I agree it should be a pretty low, but maybe not that low. I just measured my water: 1200 PPM after the water softener, 110 PPM at the drinking water tap. Directly after the RO membrane when it is actively running, the reading is 60 PPM. My RO membrane is advertised as providing a 95% reduction in TDS, which matches my measurements pretty closely (60/1200 = 5% remaining, so 95% reduction).

"TDS creep" is the reason the water we actually drink is 110 PPM and not 60 PPM. Some TDS creep is normal in RO systems that store water. There are ways to reduce it.

My bad. I meant to write " before and after the softener."

I just measured the TDS of the softened water at 847 ppm. That is a bit lower than usual. But it does vary a little. The RO water is reading 36 ppm. That is the first few oz from a line with a 1 gal reservoirs. That's 96%. Over time, I can see and taste a bit of dried salt residue left in the catch bin under the RO dispenser in the fridge.

Just for fun, I measured some distilled water at 000ppm.

 

[CardsFan]

Just for the record: Pure water (distilled, or out of an efficient RO unit) is tasteless and highly corrosive. Because it has no minerals, it will try to extract them from any thing it touches (such as lead pipes). It also has no residual chlorine, so if it gets contaminated, bacteria, etc will grow quickly. Fine if it is in your fridge. Not so fine if it is in your Keurig, warming, for 3-4 days.