What’s in the water?

I promised in the last post that we’d spend more time talking about various chunks of water chemistry, a very broad overview, as it relates to dye chemistry. In specific, madder dye baths. Well here we are, another post about water. Today we’re going to have a quick look at Total Dissolved Solids, or TDS.

Photo by Snapwire on Pexels.com

I measured the TDS values out of all of my samples with a basic meter (acquired off of Amazon), and gave it a rinse with distilled water between each sample. It was the meter that gave me the least grief throughout the entire experience, so gold star to my little TDS meter.

When we’re discussing things that are dissolved in our water, that is exactly what the TDS measure is. Total Dissolved Solids, which describes the both the inorganic salts and the small amounts of potential organic material present in the water. This could be a while assortment of things, but are usually calcium, magnesium, sodium cations and carbonate, chloride sulfate anions, amongst others. While TDS is often assumed to be a measure of quality, it is less discriminatory than that. It only measures that something is there, not what that something is, nor if that something is harmful, or unpalatable. The WHO has very general guidelines on palatability of drinking water with less than 300 mg/litre being considered excellent, good, between 300 and 600 mg/litre; fair, between 600 and 900 mg/litre; poor, between 900 and 1200 mg/litre; and levels greater than 1200 mg/litre being considered unacceptable.1 In our water survey TDS was measured in ppm (parts per million), which is approximately equivalent to mg/litre. The lowest TDS measured (outside of controls) was sample 37 at 27ppm, which falls in the excellent category and the highest was sample 26 at 559 ppm, which falls in the good category. A copy of my water survey results can be found linked in my google drive.

Inkbird TDS meter

Often, it is assumed that TDS is a measure of hardness, but TDS is too generalized a measure to mean only that. While it includes the minerals that are part of what is referred to as ‘hardness’, primarily calcium and magnesium, that is not all that it includes. The TDS values of the iron samples are a prime example of that (samples 63, 65-68). Those samples are distilled water with the addition of ferrous sulphate, no minerals associated with hard water present and they not only have TDS values, but it is proportionate with the amount of ferrous sulphate added. In our water samples, it is overly simplistic to assume that TDS refers to hardness, but in absence of good detection of other minerals, it is an assumption I am generally willing to make, with caveats. Certainly I do not assume TDS references hardness when the composition of the solution is known (ie the ferrous sulphate solutions). Water in Ontario is extremely variable in hardness, although we do have some of the hardest water in the country, but that is not consistent.2  Madder, as a dye, appreciates hard water, it usually promotes a deeper red colour, although interestingly, we got an exceptional colour from distilled water (sample 60), so clearly no one told my madder bath that day.

Modern dyers, when looking to augment the calcium in their water, tend to add chalk (calcium carbonate) directly, or a crushed up tums tablet or two (which is calcium carbonate, but with handy fruit flavours!), so if you aren’t super happy with the colour you get from your madder pots, give that a try. Calcium carbonate is very mildly basic, so it doesn’t affect the pH of the dye bath to any great extent.

Next up, we’ll have a look at iron, which can be contained in the TDS measure, but is interesting enough to talk about all on it’s own.


  1. Total dissolved solids in Drinking-water; Background document for development of
    WHO Guidelines for Drinking-water Quality
  2. Guidelines for Canadian Drinking Water Quality: Guideline Technical Document – Hardness

Water Survey results pt 1

I’m not going to bury the lead on this one, now that I’ve taken my many many skeins of red yarn to show people at last weekend’s Kingdom A&S in Ealdormere, I’m happy sharing it with the blog world too. This is going to be a series of posts over the coming weeks. Starting with the pretty colours today, but then continuing into the water chemistry that affects the dye baths over further weeks. We started that last time with pH, but we’ll also touch on dissolved solids, iron and chlorinated water (and whatever else comes to mind as we go).

I detailed out the premise of the experiment in this blog post, but long story short; in late 2021, I had a hare brained scheme to request water samples from all over the kingdom (and beyond!) to do a selection of dye baths from to illustrate the variation that could be obtained while only changing one variable, the water. Note that photos do not do any of these colours justice, come see my samples at in person events!


With 68 samples to work through, it was clear that a traditional ‘pot on the stove’ style of dyebath for each one was not at all going to be feasible. I have used a water bath method to do batch samples before and it is very effective.

For each water sample the pH, TDS and iron content was measured and noted down. The sample then had 600 ml measured into a clean (rinsed with distilled water) glass jar, if the sample contained less than 600 ml, it was topped up with distilled water to a total volume of 600 ml. Each of these jars had 3 g of madder powder added to them. The water bath was set up to hold 15 jars per batch, and the water temperature was held constant at 65C with a sous vide appliance. The dye liquor was brought up to temperature, and then held at 65C for two hours.

The yarn had been skeined off, weighed dry, mordanted in batches with alum at 10% wof and dried. Before dyeing, the skeins were soaked in distilled water to ensure they were fully wet.

After the dye liquor had steeped for two hours, the wet wool was added and stirred with a disposable bamboo skewer. The wool was held at temperature for an hour (stirred again at 30 minutes for Batch 2-6), and then was removed from the water bath after the hour had passed. The wool remained in the dye bath to cool naturally overnight. After 12 hours of cooling, the wool was removed to a drying rack to dry. The wool was left to dry for approximately 10 days before rinsing with distilled water and being left to dry again.

Everything was recorded in a giant spreadsheet that you are welcome to have a look at here.


We had a quick look at the equipment that I used over in another blog post, go have a look there for all of my meters and strips and the like. The only addition to that list is my newest toy, a Color Muse colour meter. This little gadget is designed for interior designers to be able to match paint to fabric swatches, but also very helpfully provides a standardized reading of colour. The one that I’ve chosen to use is the CIE L*a*b* colourspace, which is specifically designed for comparisons. More on that in a future blog post, I have done little beyond take the readings at this point.


The main form of showing my results is the photo at the top of this post. I embroidered a map of the relevant section of Ealdormere and then tied a loop of wool in the approximate location of its water. (Linen map, outlines in walnut dyed silk, compass point also in silk dyed with indigo, cochineal and mystery yellow.) The sample cards are a little bit easier to look things up and compare numbers and those are arranged by dye batch, shown below.

We’ve started talking about the water chemistry involved, looking at pH first in this post. We’ll move on in future posts to talk about total dissolved solids, iron levels, chlorine in city tap water and ultimately the results of the colour meter, but I’m aiming for this post not to turn into a thesis. When all is said and done, I’ll gather everything up into one document and stick it on my website such that people don’t have to scroll through blog posts to find the information. For the moment, however, stick around for the serialized version. Questions and comments are very welcome!

Water quality and your dye pot

I’m in the depths of getting wool skeins dyed, and don’t have any of that ready to show to the world yet. Its a lot slower and more complicated to get from water sample to dyed wool when taking measurements at every step on the way, but it’ll be good in the end. Hopefully I can remember to stir the next batch more so they are less blotchy. <sigh> But I digress! There’s three main things I’m looking at in the water: pH, Total Dissolved Solids (TDS) and iron content (ppm). Let’s have a chat about each of those in turn and today we’re going to chat about pH. There’s a lot of complicated chemistry involved in water, and there’s quite a bit of interplay between all three (and temperature, and and and).. I mean, you can get a whole university degree in water, so know that we’re aiming for broad strokes here and big picture.

The pH Scale of Common Chemicals

The one that most people are familiar with on any level is pH, the measure of how acidic or basic something is. It’s measured by looking at the free hydrogen ions (H+) in the solution. (Inversely proportional, as a note: More hydrogen, lower pH.) It’s a scale that runs from 0-14, with acidic things down low and basic things up high. Pure water is the control, and it sits at 7.0. A few things people don’t realize (or remember from high school chemistry) is that the scale is logarithmic, which basically means that the distance (or number of hydrogen atoms) in going from 7 to 6, is not the same as the distance from 6 to 5. There’s 10 times as many in that second chunk. That’s trivia level content more than super relevant to anyone reading, but if you ever wanted to try and count hydrogen atoms.. well we can talk about new hobbies, hmm?

When reading the WHO Guidelines on drinking water (1) , a pH anywhere from 6.5 to 8 is considered acceptable. Pure water, remember, hangs out at 7 exactly, but there’s a lot of elements that affect the pH without making the water undrinkable. All of us who lived through the pollution filled 1970s and 1980s remember the screams about acid rain and how it was melting away everything, I think. Pollution can affect the pH of water, but by the same token, most ground water has absorbed enough minerals that it slides itself a little higher on the pH scale. (And you pay extra for all those minerals at the store when you buy spring water.. s’okay, they are generally what makes water taste better. Distilled water always tastes flat and weird.)

So clearly everything below 6.5 and above 8 is dangerous, right? Well, not so fast. Where it gets more complicated is that pH alone is not an indicator of safety. Common household vinegar has a pH of approximately 2.8, which is extremely low.. in the same range as stomach acid, but we think nothing of ingesting vinegar (ideally on a nice hot plate of fries.. mmmm.) It is a weak acid, a well diluted acid, generally sitting at about 5% strength. If it was full strength, it would be very dangerous indeed!

Further complicating matters is how pH and other measures interact. pH is extremely dependant on temperature (not much of a consideration for me, all of my samples were at room temperature), and the pH of water can determine its tendency to have picked up other ions. As the pH gets lower, the metals are more soluble.. they dissolve more easily in the water, so there tends to be more lead, copper, iron etc in water that tends towards the acid. We’ll talk more about metals in water when we have a better look at the iron testing that I did and how that affects the dye works.

Water chemistry is complicated and while I knew it was a big field to go poking into, it’s been a fast train into the depths. It’ll take a lot more digging to get myself out of these weeds.


  1. World Health Organization – pH in Drinking water (2007)
  2. Safewater.org TDS and pH (2017)
  3. Health Canada – Guidelines for Canadian Drinking Water Quality: Guideline Technical Document (2015)

Natural dye gear

Today, we’re going to talk about gear. Most posts are about how little you can get away with as not to scare off the beginners, and those posts are amazing! (A pot dedicated to dye work, a couple of spoons, a scale. That’s pretty much the minimum. Go forth and be awesome.) This is not that post. This post is about the gadget fond dyer, the one who likes too much information. The water project (I talked about it back in this post.) is pretty much using all of my fun gear beyond the basics, so let’s have a look at what I’m using there.

Alright, let’s break this down by bits. The first thing we’re going to talk about is the weird cylinder thing at the top of the photo. That is my sous vide. It is basically a very fancy aquarium heater, capable of holding a pot of water at a specified precise temperature for a very long period of time. When I am doing large sample sets, I put my samples in jars and then place the jars in a water bath. That lets me do 10 or more samples at a time.. which is a whole heck of a lot faster than one at a time! It is not fast, I will say that about water bath dye work. It takes a lot longer for things to get to temperature than it would if I plunked a pot on the stove, but I also can walk away for hours and know that it will hold at exactly the temperature I’ve set it for, because that is literally what sous vide appliances do. (Not shown: The plastic bin I plan to use to hold my water bath. It’s a short rubbermaid tote. You all know what those look like. Also not shown, the glass jars that hold each sample. They are clean spaghetti sauce jars. You also all know what those look like.)

In the second row of things, starting from the left is a tube of iron test strips. (For things I got off Amazon, I’ve linked to Amazon. No affiliation, no kick backs, no promises that I picked well.) These measure soluble iron, so the Fe molecules that are hanging around waiting to cause trouble (aka react) with things we dye with. They measure in parts per million (ppm) and while I am not fond of colour compare (more on that with the pH strips), they’ve worked fairly well for me in other experiments to this point.

Next in the lineup are my pH strips. This was not the plan. I have a perfectly nice pH meter, acquired from the brew store, and I was all excited to use it. Except that the probe got damage (poor storage at the store mixed with no better storage at my house.. it’s fubar). That’s fine, this pH meter has a replaceable probe for exactly this reason! Probes do not last forever, this is a known thing! Awesome! Oh wait.. it’s only available (right now) in Australia, from a company that does not ship outside the country. Chatting with the Canadian distributer, he asked me to call him if I found any in Canada that he could get his hands on. Right. Thank you supply chain issues. No pH meter. Alright then, pH strips it is.. I hate them. I find them hard to read, the colours are hard to distinguish, and I eternally question their accuracy. Better than the nothing I was facing, but know I am not in a happy pH place.

Next up is my newest gadget.. a TDS meter. Total Dissolved Solids, basically it gives a measure of the hardness of one’s water by looking at the conductivity. Salts and minerals increase the conductivity of water, and so can be measured. Does it tell you WHAT salts and minerals are there? Nope, it sure doesn’t, but it does give a general idea on how much. Not a perfect measure, but gives us a ball park to play in. Which is, honestly, not half bad for kitchen chemistry. I am not set up in a lovely lab with a handy procurement clerk down the hall that I can go request all the bits my heart desires from.. I have amazon and my kitchen. So we’ll manage.

I’m going to hope that everyone reading recognizes a basic thermometer. It clips on to the side of a pot, and lets me keep an eye on the temp of the dye bath. You can tell that it’s seen hard use based on the colour, but it still works fine.

Last but by no means least, are my scales. They are the overlap between basic kit and this one and yes, there are two pictured there. The bottom one measures in grams, and is crap less than about 10 g, but can manage a chonk 7 kg. The top one is my delicate little scale, it measures 0.00 grams, and gets the vapours if you go over 200g. When you work in sample sizes, the tiny little scale is a necessity. (A 6 gram skein would want about 0.6g of alum. None of this is possible on my chonk scale, but the teeny one thinks this is /fine/.) Everything else is fun information gathering, the scales are required equipment.

So there you have it, the extras that I’m growing fond of (other than the pH strips, those are a necessary evil). Questions? Comments? Let me know some of your favourite gadgets!

Water, water, everywhere!

My first major project for 2022 is one that I’ve wanted to do for a long while, and I’m getting a whole lot of help with. How big of a difference does water source really make in one’s dye projects? Well! I decided to experiment with that premise, and asked people to share a water sample from their house. (And barns, streams, lakes..) My reenactment group is very generous and now I have water samples from all over the province, and beyond! 60 samples! I was hoping there’d be 20 or so, I certainly have my work cut out for me.

A messy studio made messier by a lot of bottles of water.

The basic experimental premise is very simple. Keep all the other variables steady (or known at least) and have the water as the main variable. Measure as much as I can about each water sample, to have some idea on what it contains, but then keep the dyestuff, the method, the fibre, the mordanting.. all of that to be the same so that differences can be safely assumed to be because of the water.

Which dyestuff to choose was an easy one. Madder is delightfully reactive to changes in water hardness, and pH and generally is a bit of a fussy goose, so it’s perfect for this. I got a nice big container of R. tinctorium, so that all 60 samples can be taken from the same batch of powder. Natural dyes are variable in and of themselves, from one batch to the next. The growing conditions, the soil, how the plant was handled and the dyestuff extracted all can affect the dye that I’ll be using, so at the very least, this one container should be relatively homogenous, even if multiple batches of madder went into it.

Fibre was also a no brainer choice. I’ve worked up small skeins of 100% wool yarn, all of which has been mordanted at 10% wof with alum. Basic, easy, nothing fancy going on here. Wool and alum. Done and done. The skeins aren’t quite perfectly consistent, they range from about 5 and a half grams to about 7 and a half grams, but I’m willing to be ‘close enough’ on that one.

Grocery bins are eternally handy.

I’ve had very good luck with using a water bath to keep my temperatures very consistent, as of course madder is also sensitive to what temperature it’s dyed at. Basically a large tub of water is heated with an immersion heater (sous vide gadget, I do love you and not just for steaks), and each dye bath lives in its own glass jar within that tub of water. I used this method for one of my earlier madder experiments and it worked a treat. I will have to work in batches, as I can’t fit all 60 at once, but good technique should keep that variable to a minimum.

Then it comes to the water itself, and there’s lots of it. The plan is to grab the pH, the iron content and a general measure of hardness (Total Dissolved Solids) from each sample. This should give me a moderately good idea on what’s going on in the water itself. I will admit freely that it is not ideal that the water has now sat for a good six weeks before I’ve gotten to working with it. (Thank you holidays and general life challenges.) Stale water means that I’ve lost most of the volatile compounds that would have been in it, and any that were treated with chlorine (rather than chloramine), that’s absolutely gone. Some of the unfiltered water has sediment that has settled out while it’s sat, and while I do plan to give each a shake before I measure it, it’s not quite the same as fresh. Still, this is what I have, and the reality of collection means that there was always going to be some sitting time before I used it. So be it, we’ll manage.

So expect more on this project in the hopefully near future! I think I have all of the pieces in place now, so it’s just a question of getting to the doing part.