Tap Water vs Distilled Water Experiment

Soapmaking Forum

Help Support Soapmaking Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
Does anyone here test their own water or make their own distilled water?

I have a TDS (total dissolved solids) meter that I use to test the water for topping up my marine aquarium. It measures the total dissolved minerals and salts within your water. The idea in the coral hobby is that the TDS in your water should be 0 and you then add your salts etc. At my old house my water measured 7mg/L which is pretty low anyway but for the fish tank I still invested in a reverse osmosis water distiller (RODI) system from Amazon, was only a couple of hundred dollars but it allowed me to store distilled water with 0 TDS in a 200L tank to use whenever I needed.
I used the same water for my soap as it was filtered via reverse osmosis and then distilled so it was perfect.

Now I have since moved house and we are on tank water here. We live in the Blue Mountains west of Sydney Aust and the air and rain water quality here is excellent. I have measured the rainwater tank with my trusty TDS meter and it measures 0.3mg/L. I feel this is good enough and have been using it for the past 11 months and have not had any problems so far. I still have bars of soap I made from every batch since living here and I haven't seen any issues develop over this time. Hopefully all will be well and I can continue to use my rainwater.
Does anyone else here use rainwater?
 
Does anyone else here use rainwater?
Here’s something crazy—only very recently in Colorado were the laws changed so that you can collect and use rainwater that runs off your roof. Before that it was illegal, because that water was owned by someone “downstream” of you. Water laws in the western US are wacky.
 
Here’s something crazy—only very recently in Colorado were the laws changed so that you can collect and use rainwater that runs off your roof. Before that it was illegal, because that water was owned by someone “downstream” of you. Water laws in the western US are wacky.
I'm in Oregon and you can ONLY collect rainwater off your roof.

And in my town, we also have what we call a "rain tax" that is tacked on to our sewer bill; the actual name of it is "Storm Water Utility Fee". It is based on the size of your lot and how much of the lot that is covered by buildings (house, garage, outbuildings, driveway (asphalt/concrete). The less open ground you have, the higher the tax...umm I mean fee you will pay because less open ground means more water in the drains. Ours is fairly cheap as two-thirds of our lot is grass. My neighbor across the street, their lot is half the size, but they pay twice as much because they only have have a small front and side yard.
 
Here’s something crazy—only very recently in Colorado were the laws changed so that you can collect and use rainwater that runs off your roof. Before that it was illegal, because that water was owned by someone “downstream” of you. Water laws in the western US are wacky.
That is nuts!
 
I'm going to upload my photos here. I can move them if needed.

5/13/22
Oils:

Palm, Olive, Sunflower HO, Palm Kernel, Cocoa Butter, Coconut, Rice Bran, & Castor

Additives:
Sorbitol, Sodium Lactate, EDTA, Sodium Gluconate, Sugar, & ROE

Colorant:
Dolphin Blue mica (WSP – Crafter’s Choice), ~30% portion of batter, 1/8 tsp mica
Uncolored ~70%

Distilled Water (DW) Design:
Infinity Swirl (kind of)

Tap Water (TW) Design:
Pseudo layered, pipe divider, and ITPS??

Mold:
Little wood boxes from Hobby Lobby lined with freezer paper.

Oil Weight:
12oz

Oil/Lye Temps:
TW: 90/96
DW: 89/94

36% Lye concentration.
Lye was mixed fresh for both. No difference in appearance or behavior between TW and DW.

Batches were made within 20 minutes of each other. Waited until soap had a dull appearance to cover and wrap with plastic wrap. Placed both on a rack under a ceiling fan.

5/15/22
Removed soap from mold. No ash.
Left uncovered overnight.

5/16/22
Since the soap was poured about one bar thick, it was only necessary to cut each batch in half to get two bars per mold. However, I decided to use my single wire cutter instead of a planer to even out the top of the bars. The DW bars cut fine, albeit a little firm, but I broke my cutter wire cutting the top off the first TW bar. The TW bars did seem firmer to cut than the DW bars, but I can’t be sure if the bars were harder or if it was because the wire on my cutter was getting old.

Uncolored portion of soap - In real life the bars look the same, but when I was cropping my photos I thought the white portion on the TW bars looked a tad-bit more cream colored than the DW bars. I don’t see the difference in person so maybe it’s an optical illusion due to the TW bars having larger areas of uncolored soap.

Front named.jpg


Back - named.jpg
 
I'm going to upload my photos here. I can move them if needed.



Uncolored portion of soap - In real life the bars look the same, but when I was cropping my photos I thought the white portion on the TW bars looked a tad-bit more cream colored than the DW bars. I don’t see the difference in person so maybe it’s an optical illusion due to the TW bars having larger areas of uncolored soap.



View attachment 66834
It might be the lighting or not, but I think on this back photo, the tap water is a lot more cream colored. Thanks for the experiment and the visuals.
 
I'm really glad you're doing the experiment and I look forward to seeing how they age as well. May I make a suggestion about the lighting question? Switch position of one tap water bar with one distilled water bar. If there is a lighting issue it will be easier to identify.
 
I'm really glad you're doing the experiment and I look forward to seeing how they age as well. May I make a suggestion about the lighting question? Switch position of one tap water bar with one distilled water bar. If there is a lighting issue it will be easier to identify.

@Dan9250 Thank you for the suggestion. Based on these pics they do look the same, especially the side view.
Obviously my photography skills need work!

IMG_8169.JPG
0519221151.jpg
Water test 05.19.22.jpg
 
Is it just me or do the tap water ones look slightly smaller? I've also noticed that the color seems different between them. But only slightly. Not sure if it's the photography or not.
 
Is it just me or do the tap water ones look slightly smaller? I've also noticed that the color seems different between them. But only slightly. Not sure if it's the photography or not.
The colors are tricky to catch on film, at least for me any way. In my original post I had a hard time getting a good photo as well. I'll try to take more pics today.

I think you may be right about the bubble size. The DW bubbles are slightly larger and not as dense.

Here are the same photos from above as separate photos so they can be viewed enlarged.

20 Second - Distilled
0528221354d.jpg


20 Second - Tap
0528221353a.jpg


50 Second - Distilled
0528221354g.jpg


50 Second - Tap
0528221353c.jpg
 
Second-ish week update: still no huge discernable difference. There is a slightly more pleasant (sweeter?) scent to the tap bars, both when they’re dry and sudsed up. I’m a little surprised how the red clay bars for both tap and distilled out-suds the plain bars.
 

Attachments

  • 2F39B6F3-BAE7-4B84-8F48-FFD078D8E6EB.jpeg
    2F39B6F3-BAE7-4B84-8F48-FFD078D8E6EB.jpeg
    119.3 KB · Views: 0
  • ABC66EE8-6622-4E61-8B39-5AC007E9089C.jpeg
    ABC66EE8-6622-4E61-8B39-5AC007E9089C.jpeg
    137 KB · Views: 0
  • A3AC01F1-37BA-4369-94AD-4E8721F0AFC2.jpeg
    A3AC01F1-37BA-4369-94AD-4E8721F0AFC2.jpeg
    127.1 KB · Views: 0
  • A3A94C60-5FE2-42A1-A692-AC6CCFF0BFA6.jpeg
    A3A94C60-5FE2-42A1-A692-AC6CCFF0BFA6.jpeg
    132.5 KB · Views: 0
Results at 7 weeks:
No change in appearance in either bar, both healthy.

T 0703221132_HDR.jpg
D 0703221135.jpg


20 seconds:
Distilled Water (DW) lather was a little more than Tap Water (TW). However, they were pretty close, maybe not enough to matter at this point?

T-20_0703221134a_text.jpg


D-20_ 0703221136a_text.jpg


50 seconds:
DW lather was thicker, denser, and I noted that there was more lather falling from my hands.

T-50_0703221135b_text.jpg


D-50_0703221137a_text.jpg
 
Results at 9 weeks:
No change in appearance in either bar, both healthy.

Something interesting happened that I hadn't noticed on previous tests. When I finished doing the lather test, I noticed some scum had formed in the sink. My immediate assumption was that it must be the tap water bar. I reviewed my log sheets and realized that I had under-calculated the EDTA/SG; I based it on the total oil weight not the batch weight. So I cleaned the sink and lathered up the tap bar for 50 seconds (same length of the original test) and noticed there was some scum building back up in a small area. I scrubbed the sink again and lathered up the DW bar for another 50 seconds and much to my amazement there was much more soap scum (heavier coating and a larger area) than the TW bar.

Curious, as to why the bar made with tap water would have less soap scum? Now I'm thinking maybe I should do another test with no chelator in either, although I don't know how much more that would tell me. I mean, I can already see that the TW bar developed less scum. What say you all of my soapy science geeks?

T 0716222053a.jpg

D 0716222056.jpg



20 seconds:
Distilled Water (DW) lathered quicker with denser lather.

T-20_0716222054b_text.jpg

D-20_0716222056c_text.jpg


50 seconds:
Bubble size is pretty close, but DW had more lather falling from my hands.

T-50_0716222055c_text.jpg

D-50_0716222057_text.jpg
 
Back
Top