I’m frequently asked about why soft water is “slimy”. Some people will tell you that you’re feeling your natural body oils when washing with soft water. Body oils play a VERY SMALL part in the feel issue. Slimy feel is really affected by water pH, carbonate content, sodium content and of course the type of soap being used.
Soft water (for most applications) is water that contains less than 1 Grain per Gallon (GPG) of Calcium Carbonate hardness.
Hard water contains calcium and magnesium ions. When you use soap (real soap, not a Synthetic detergent/surfactant) in hard water, the soap will react dramatically with the hardness to create that rough sticky precipitate known as soap scum or soap curd. Soap curd sticks to everything that it touches…skin, hair, clothing, bathtubs, shower curtains, shower stalls etc… it is a general nuisance and visual evidence of hard water’s inability to clean properly.
When you use real soap with soft water, there are no ions to react with the soap and it lathers quite spectacularly. The lather is evidence of preserved cleaning power. That is why softener salesmen can make claims like “whiter whites, brighter brights, and darker dark’s” – it’s actually true.
Of course, there are different kinds of SOFT water…
- Naturally soft water – Water that is naturally devoid of hardness ions. Rainwater is usually a good example of this
- Ion exchange softened water – Water that has been processed using ion exchange to replace hardness ions with sodium or potassium.
- Chemically softened water – Hardness ions ore sequestered chemically by chelating agents like Sodium Tripolyphosphate (STPP) – Do you remember Calgon ?
- Purified Water – Water “purified” through a distiller, reverse osmosis nanofilter, electrodeionization(EDI), or CDI array. – the hardness ions are physically removed, but not replaced with anything else.
This is where things scan get confusing, since these types of soft water react DIFFERENTLY with soap.
- Sodium Ion exchange softened water will feel slimy with most soaps, since they are made from lye
- Sodium Ion exchange softened water will not feel slimy with potassium-based soaps like Dr Bronner’s Potassium Hydroxide liquid soaps.
- Chemically softened water will usually feel slimy
- Naturally Soft water rarely ever feels slimy with sodium or potassium-based soaps
- Purified water rarely ever feels slimy with sodium or potassium-based soaps
- If you use a high pH soap, it will feel slimier than a low pH soap.
Regardless of the amount of hardness in the water:
- Low pH soft water will feel rough, no matter what.
- Low pH is bad since it neutralizes itself by corroding pipes, fittings, fixtures and appliances.
- High pH soft water will generally feel slick/slimy. (Try adding varying amounts of baking soda to a bowl and washing your hands in it).
- If your soap has high levels of oleic moisturizers, then you can even get a “greasy” feel if the pH and sodium levels are high enough.
- Carbonate Alkalinity will change the feel of the water, as well the effectiveness of various cleaning products.
Here is a list of different soaps and their average pH
Camay 9.5
Dial 9.5
Dove 7.0
Irish Spring 9.5
Ivory 9.5
Lever 2000 9.0
Palmolive 10.0
Zest 10.0
So when you’re looking for more or less slime, consider the above and enjoy your clean water!
Hello,
I live in Hanford, Ca where the water has hydrogen sulfide. They have chlorinated the water to remove the sulfur smell, however it is slimy. Do you have recommendations on which filtration systems can help remove the sliminess?
Appreciate any insight you can share.
Vidhu
Very helpful. Thanks
Every site I have read about slimy soft water talks about after using soap in some way. THIS SLIMINESS HdAS NOTHING TO DO WITH SOAP! When I run my hand under my ‘soft’ water without any form of soap it feels SLIMY. This seems to happen about 2-3 weeks after adding more salt, lasts a week or so & then sliminess is gone. DOES ANYONE HAVE A REAL REASON FOR SLIMY SOFT WATER???
Hi Lynn, thank you for your passionate comment.
The phenomenon that you’re describing is quite different from the scope of my “Slick and Slimy Soft Water” article.
Water can and will feel different aside from soap, but within the scope of the article, we’re discussing the interaction between the constituents of soap and the ion-exchange byproducts in soft water.
When not considering soap interactions, the feel of the water is usually affected by the pH and total alkalinity of the water. Acidic water (pH below 7.0) will tend to feel rough, and alkaline waters (pH above 7.0) will feel smoother. As the pH rises (>8.0), the water will feel slick and sometimes even “slimy” depending on what else is in the water.
One can experiment with this phenomenon by filling a mixing bowl with water and then adding small amounts of baking soda (about 1/4 teaspoon at a time) and observing what the water feels like as you raise the pH by adding more of the baking soda. The opposite effect can be experienced by adding white vinegar in similarly small amounts to observe the acidic feel of the water.
Addressing your specific issue: Without water testing and observation of your water softener, it is tough to give you a definitive explanation of what is happening. I suggest you contact your local WQA certified Water Specialist to evaluate the system for you. I wouldn’t be surprised if your system’s cleaning cycle is causing excess alkalinity to remain behind after the system cleans itself, resulting in the “slimy” feeling that you’re noticing.
Hi Vidhu, the best course of action is to test the water for alkalinity and make decisions from there. 5-in-1 test strips like these: http://www.hach.com/5-in-1-water-quality-test-strips/product?id=7640211609 are a good place to start. Once we get a handle on the pH and alkalinity, we can look at potential solutions.
After reading all this info I’m still confused. Please make it simple. I hate the slimy feel. I do not want the slimy feel. Should I use Dove at 7.0 or Zest at 10.0?
Hi Phillip, choose a soap with a lower pH for less of a slick feeling. Using potassium salt in your softener will also help you to reduce the slick/slimy feeling.
Installing a dealkalizer or switching your softener for an Enhanced water filtration system are more expensive options, but will work extremely well.
I’m very impressed with the completeness of you post and answers. I have observed one thing that does not seem to fit the comments about soft water leaving the skin clean and hard water leaving rough crud on my hands. If I wash in soft water and get the slimy feeling on my hands and then rinse for two more minutes, it comes off. Also if I wipe on a clean towel (washed in soft water) the slimy feeling goes away quickly. Any thoughts?
Hi Joe,
Your experience is consistent with a high pH soap not rinsing all of the hydroxide off of the skin immediately.
If you want to do a little experimentation, take a look at the soap pH scale and try different soaps then observe the difference.
All the best,
Greg
Hi Phillip, the lower pH soaps will feel less slick, and potassium-based soaps will feel even less slick.
All this is talking about skin. when I wash a pan I get the same thing the pan seems feel slimy when rinsing. The water seems to be removing the calcium form everything too. The inside of my dishwasher is sparkly clean now. if I take the cutlery out damp it feels slippery when I pick it up. Does this mean I am using to much salt?
Soft water itself doesn’t feel significantly different from hard water until soap is involved, so you might possibly have a pH or alkalinity issue. One thing to try first is reducing your soap/detergent by 50% and trying again to ensure that the soap residue rinses off completely.
Hello, thank you for the article.. I used to live in SF and have the soapy\slimy feel. And I prefer that. I moved to Portland and have been through 3 softeners and none of them are giving me that feel. Is there a reason why I cant achieve that?
Portland, OR has water with a relatively low alkalinity and baseline hardness, so traditional ion exchange softening will not have much effect on making the water feel “slick” at all. – Even though the water is actually soft.
To make it feel slicker, you’ll have to add some alkalinity to the water with an injection pump.
You can experiment with this phenomenon by washing your hands in a 1 Gallon bucket of your water, and then doing the same thing after adding a tablespoon of baking soda to the water. You’ll notice after the soda addition, the water will feel slicker/smoother. – interesting phenomenon.
Very concern about our well water…we use our coffee maker that’s got to be filled with water and if any is left in the tank where water goes, in two days it’s really slimy filling and even when we make tea in a plastic pitcher….it gets slimy in two to three days…..kinda getting worried about putting in our body’s🤔…..Please Help Us….and let us know what we could do if you know….Thanks…..Scott & April Smith🤗
Wow, that doesn’t sound good at all. It sounds a lot like Heterotrophic bacteria (HPC), which are not in themselves dangerous. However, they can often indicate the potential of other contamination. The very best thing to start with is a water test and consultation with a Certified Water Specialist. What ZIP code do you live in?
After reading your articles, you have answered our questions on why our public water feels slimy. I do have another question. Is this water really safe to drink or cook with? Example: fixed some instant grits a few weeks ago and they were orange colored on top but looked ok in the middle. Thank You
Water in the USA is some of the safest in the world.
Naturally, bad things can happen along the way after it leaves the city plant until it comes out of your faucet.
Orange specks might indicate the presence of iron or iron-related bacteria.
Consult with your local Certified Water Specialist (CWS) to have your water tested and find out ways to make it cleaner and safer.
http://www.wqa.org/find-providers
Hello Greg, I have a new well with hard water so am learning about various treatments and am particularly focused on avoiding, or at least minimizing, the slimy water feel. You state, “Sodium Ion exchange softened water will feel slimy with most soaps, since they are made from lye” and “Purified water rarely ever feels slimy with sodium or potassium-based soaps”. If the primary difference in these two types of water is sodium, is it then fair to conclude that it is the sodium mixing with the soap that imparts the slimy feel? If so, perhaps an Ion exchange softener followed by a whole house R.O. system would be the way to go. (But I also have dissolved rust I think – need to get water tested.) Your article lives on! Jim Wangerin
Hi Jim! – Yes, sodium bicarbonate in the water interacts with the sodium-based soap to create the slimy feeling.
Reverse Osmosis after the ion exchange system would certainly address excess sodium ions, but the capital expense can be a deal-breaker for some.
Definitely get your water tested for at least the following: Hardness, Iron, pH, Total Alkalinity – this will help in proper selection and sizing of treatment.
I actually prefer hard water. What I don’t like is all the deposits it leaves. Is there a way to remove whatever is leaving the deposits (limestone , calcium) without using a traditional water softnet?
Hard water scale can be effectively prevented in most areas by using Salt-free scale control technologies like Next ScaleStop or Active Armour. Both are designed to control scale formation and hardness adhesions, but not physically remove the calcium/magnesium hardness from the water. Since these are not softening technologies, they will not help with laundry, dishes, or other soap/detergent applications.
Hello Greg, I’ve been battling with water issues like this for a good 12 months now and I’m happy I found this page because I am so confused why this is happening… When this problem started, we had hard water (around 180 ppm), I noticed I couldn’t rinse this soapy/greasy feeling out of my hair or off my body. I did some research and finally bought a water softener thinking it would resolve my problem… However, it almost made this problem worse? I’m wondering if it could have anything to do with the PH, or if you know how I could possibly fix this! Thank you again !
That sure sounds like a frustrating situation.
Elevated pH will make water feel slicker with soap, even with 180 mg/L of Hardness in the water. By softening you’re removing that hardness and adding Sodium Bicarbonate to the water which will make it slightly more basic and raise the Total Alkalinity.
Your experience suggests that it might indeed be a pH issue.
Get some cheap pH strips and see what the pH level of your hard water, soft cold, and soft hot water is, that will help us understand you problem a little better.
pH can be adjusted using various methods, are you on well water or city water?
Another thing to try while you’re digging into the pH levels is to use a potassium-based liquid soap like Dr Bronner’s – many people report significant improvements in the feeling in the shower when doing that.
Keep us posted and we’re all excited to help you figure this out!