What Causes Etched Glasses in Dishwashers
What Causes Etched Glasses | This drinking glass of mine used to be crystal clear. Cascade dishwashing gel ruined it. This column was SO GOOD that I shared with the 31,000 subscribers who read my October 4, 2020 newsletter. Copyright 2020 Tim Carter
Author Update: Don't skip over the last paragraph below from Brad Booth.
What Causes Etched Glasses - It's Chelants & Cascade
QUESTION: Tim, please help me. I remember reading in past columns that you’re a master plumber and have some sort of science degree.
My husband and I are at odds as to what’s slowly ruining all of my wonderful clear glasses and heat-treated glass items in my kitchen. Each time I remove them from my dishwasher, they look worse. My husband states it’s just hard water.
I tried soaking some of the ruined things in hot white vinegar and there was no change. It’s got to be something else, but I can’t figure it out. Can you shed light on this? Sandra P., Las Vegas, NV
Are you suffering like Sandra? I am! The clear drinking glasses in my own home are slowly getting ruined just as Sandra described. Sandra’s correct that I’ve got lots of experience with dishwashers being a master plumber since age 29 and having worked in a commercial kitchen operating a powerful chili parlor dishwasher for over 12 years. A five-hour physical chemistry class was a requirement for my geology degree.
The glass on the left is brand new. The one on the right is etched beyond repair. Proctor & Gamble's Cascade dishwashing soap is to blame. Photo credit: Tim Carter Copyright 2024
Is the Cause Hard Water?
Many years ago, I was first introduced to this strange conundrum by my mother-in-law. I was a brash young man and she showed me one of her ruined small drinking glasses. She asked me if I knew what was going on. “Sure, it’s just hard water deposits. Let me take it home and restore it.” I tried soaking it in white vinegar, a mild acid that has no trouble dissolving hard-water mineral deposits. There was no change. I then got out my toxic bottle of muriatic acid and tried it full strength. There was no change. I was flummoxed.
As time passed, I deduced the issue had to be with the actual dishwashing detergents - be they powders, gels, or pods. In all my years of washing glasses by hand, they never suffered from etching, so whatever was happening was happening inside the steel box with the thrashing water spray.
Automatic Dishwashing Soap Etches Glass
Last month I finally had it. I reached out to what I believe is the largest USA manufacturer of automatic dishwashing soap, Procter & Gamble (P&G). They make the Cascade product I use. Since I’m a member of the working media, they were kind enough to accommodate my press inquiry.
A senior scientist from P&G explained that a perfect glass-etching storm can happen inside a dishwasher if you have these four things: soft water, low soil load, high temperatures, and chelating agents. She went on to say, “Chelating agents, or chelants, are a major part of auto-dishwashing formulations because they form soluble complexes with calcium and other metal ions, enabling them to remove food soils and limescale, soften water, and boost hygienic cleaning action.” When you soften water as I do at my home, you remove the calcium from the water. Uh oh!
To prevent glass etching, she suggested not rinsing dishes and glasses, wash in shorter cycles, not using the pots-and-pans or sanitizing settings, and using a dishwashing product that contains zinc.
The bottom line, in my opinion, is that if you want your clear glass to remain clear, you better do what I had to do as a kid. Wash them all by hand with normal liquid dishwashing soap. Your other option is to just keep buying new glasses after they get etched should you not want to wash them by hand.
AUTHOR UPDATE: Brad Booth lives in Columbus, Ohio. After reading the above column he sent:
"I just read the problem about glasses clouding in the dishwasher by Sandra P., Las Vegas. Cascade IS THE PROBLEM! I had the same problem with glasses, even coating my dishwasher filter using Cascade. Switched to Finish Powerball nine years ago and NO problem anymore! I've had no clouding of glass at any setting, temperature, or heat dry! Also, the screen filter no longer gets coated and clogged with white substance! Try any product except Cascade and see if that helps you."
Here's the Finish Powerball product. You can bet I'll be trying it:
CLICK or TAP HERE to have this delivered to your home. I DOUBT you'll find this at your grocery store.
Dishwasher Detergent Warning! Is your detergent harming your dishwasher? CLICK HERE to see what happened to my dishwasher.
Column 1371
So, what dishwashing products contain zinc?
Beats me! Do some research and report back with your findings.
I KNEW it couldn't just be hard water - but I've been wondering too. Yes, I subscribe to the "just replace it" tradition as I hate hand washing dishes. Also believe in the "just live with it tradition" as long as possible. Thanks for the info. Now will see if any dishwasher detergent has zinc.
I feel your pain. The way that automatic dish detergents are made today is a source of many conundrums.
You want hot water so that it will completely dissolve the detergent and do a better job of cleaning and sanitizing. What with the current Covid-19 virus problem, sanitizing with hot water is a necessary thing. But hot water adds to the etching problem.
They tell you to conserve water and not to run a load before the machine is full. That means a retired couple like my husband and me only runs it every other day. However, we live in a hot, humid southern (Houston TX Area) climate and bugs are a constant problem. Leave stuff on your dishes and you WILL have a problem before long.
We do have fairly hard water and I'd never before seen that as a good thing. But okay, we don't have a water softener due to cost, salt sensitivity and nasty taste.
And how the heck do I know if the product I am using has zinc or not? And why is that a problem?
So the short answer is you are damned if you do and damned if you don't. Why have a dishwasher in the first place if it is harming your dishes and you should hand wash your dishes anyway? So now my automatic dishwasher is suddenly just a large, built-in draining rack. And please don't tell me to use it as a sanitizer by doing a hot final rinse and nothing else.
What’s the point of having a dishwasher if you can’t was glasses! What dishwasher has zinc in it?
Hello Tim - this reply has nothing to do w/ cleaning glasses in a dishwasher but it may have some useful information. For very thin of fine glasses, I hand wash w/ reverse osmosis water (since our entire house is on RO water). I still noticed that the glasses would turn milky after a month or so stored on our cabinets. I then used Fit vegetable wash after washing and rinsing. After 6 months, the glasses remain totally clear. I did notice that after spraying & rinsing w/ Fit, the glass was incredibly squeaky clean - absolutely no soap residue left.
I also had etching on my newly bought clear glasses. Fortunately, I only had it happen to a few and realized in time to start washing by hand. I had also read that lemon in dishwasher detergent can cause the same problem, but I could no longer find non-lemon soaps. The brand I had used was Finish powder (without lemon but which I can no longer find; so was forced to use with lemon). I have been reduced to hand-washing my glasses and have tried using Kirkland brand dishwashing pacs. I think they etch, too, since my Pyrex glass measuring cup seems to be getting etched, as well. I might try the Finish Powerball, or just continue hand-washing my glasses. 🙁
Shortly after reading your story about glass etching and its causes we went shopping at our local Costco and there in the isle was a skid of Finish Powerball.
When i read this last week, I KNEW the solution was going to be Stain Solver. Maybe this is the only thing it cant fix? Haha.
This is exactly our experience. No longer use Cascade and use Finish. Glasses no longer get etched.
Finish Powerball "Max in 1" available at Costco.
You will get about as many answers to this question as there are days of the year. We have always used Cascade and not have had any issues at our mountain home where the dissolved solids are about 60 ppm on a well. A few years ago we bought a home on Florida's west coast. The dissolved solids were in excess of 360 ppm and all our glasses were cloudy within a month. The water was not drinkable either. Put a softener in still using Cascade and no problems since.
Hi Tim, I’m not sure of the ingredients in the Finish detergent you show, but it may be that it’s one of the few rare ones that still has phosphates in it. Phosphates were generally banned several years ago in dishwashing products (based more on knee jerk reactions and assumptions rather than real science) BUT they were not banned for industry use, I.e. restaurants. There’s another brand that still has phosphates in it called Bubble Bandit, ( also on a,Ali. And on their own website bubble and it.com) and it works like the old detergents used to, and I don’t recall glasses having the etching problem with phosphate detergents. I could be wrong but etching seems to really be a problem since phosphates were removed.
Just a thought and if it’s right, it’s nice to have an alternative!
I've been washing my glasses by hand for a long time. Curious why you said we aren't likely to find that finish detergent in our stores.
Well, because I don't see that detergent in my grocery store albeit it's not a massive one.
I use finish powerball and it does the same thing as cascade. That is not the solution. The only solution is wash them without any detergent.
It seem that cascade will also strip the plating ,probably nickel. from from aluminum tools that start as shiney. Two examples are my wife's garlic press and the aluminum hammer to prep schnitzels. One trip in the dishwasher and both were reduced to aluminum oxide which makes your hands black. They went in the trash and replacements were ordered. No more Cascade!!!!!!!
Hi Tim. I live in the UK and have followed your column for many years. I have heard about the glassware problems in dishwashers before, but never experienced it except with the Borosilicate glass that is used in oven proof cooking dishes. The 'Finish' brand is readily available here, and I use either that or the Magnum brand from our local Aldi supermarket. We have very hard tap water here in the southeast. Thanks for the explanation of the root cause of the glass disfigurement.
Enjoy your newsletter.
30 yr ago, same issue. Long story short.
Stop using detergent with soft water. Or use very little.
Now just 2, hand wash using a palm brush, mostly without soap.
I have been using Finish for a number of years now and my glasses have not gotten etched. I did not know that was the issue until reading your column today. I used to use cascade and the old glass are etched, I had no clue why, I guess i will never switch, thanks.
There's a guy on YouTube who is a self-described dishwasher nerd. He has a couple of videos that describe different problems with dishwashers and detergents and how to solve them. Spoiler alert: buy Walmart brand powdered detergent. When my current pods run out, that's what I'll be buying.
I have used Finish for a long time and my glasses are etched. My dishwasher broke and I now hand wash. To my surprise, everything was cleaner and shiner. I now use the washer as a drying rack.
I have always used Finish powerball and have discovered that local, Columbus, Ohio, stores are not selling this type anymore the past few months. You want the type that does not come as a "pod" and has no wrapping or only a foil wrapper you remove to use. I bought some from the above source to stock up but haven't used it yet. If I am right it is a Canadian product. I am suspicious that this classic or original Finish may be discontinued. Consequently tabs not may be of an older stock. I don't know it age will affect the product or not. The problem I have heard about "pods" is that the pod part may not completely dissolve and may clog the drainage hose. I have never used "pods" which eliminates almost all products except powder and these Finish tabs.
I've been using Finish in the dishwasher for maybe 5 years or more. No problems with glasses. I buy it at the local WalMart.
Tim, I switched to this Finish dishwasher soap from a previous newsletter you had, and I am so glad I did! No more glassware etching! Thanks!
I’ve used Finished for years and it also etches.