Trick for reading pH if you're colorblind

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JamesW said:
Sherwin Williams should make an app that will allow you to get a paint color based on the color from the color matching app.

That way you can paint your house the same color as your favorite pH.

Then, you just hold the vial up to the house to see if it matches.

You can tell your painting contractor that you want your house to be painted a perfect 7.8 pH and they will know exactly what you mean.
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Oh no, I think I’ve painted our house ‘algae outbreak, day two’.

But seriously, I think this is a great idea, I wonder if @Leebo could add something similar into the PoolMath app?
 
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Dirk said:
Huh. Theoretically you could use the same color picker analysis of a photo of the "elusive black dot." All we are doing with our eyes is evaluating shades of grey. The differences between a black dot, a faded black dot (a tint of black) and no dot (a very, very, almost-white, tint of black). A color picker app could do that just as well as it does with colors. To the app, tints of black are still colors.

In fact, a color picker app would do a much, much better job of that than our eyes can (the physics of light and retinas is complicated to explain, but our eyes are prone to all sorts of interference getting in the way of seeing color and shades and tints accurately). It's why TFP had to come up with the "hold it at waist level and just glance at the dot" MO, which is an attempt to circumvent that same interference.

It wouldn't be all that hard to figure out how a specific grey color translates to a specific amount of CYA in your water. Or at least when a specific grey color indicates the dot is "gone." Taking a decent photo wouldn't be cake, but certainly doable.
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Getting a bit off topic but I’ve always wondered why they didn’t adopt the secchi disk format although maybe that was their starting point.
 
NathanScrivener said:
If you have difficulty with colour matching, then why not get a half decent ph meter and use that to measure your ph?
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They require batteries and fiddling and regular calibration. I know they work for some folks, but I think Chris has a solid solution for his color challenge.
 
Dirk said:
They require batteries and fiddling and regular calibration. I know they work for some folks, but I think Chris has a solid solution for his color challenge.
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That’s right. Calibration and inter test variability are the big ones for me.

I bought one photometer based solution and it was worse than miscalibrated it was producing wildly different results with the same water sample. I have come to trust my Taylor kit and I know a few others do here too.

That said I’m all for buying a digital one if it’s one lots of people here trust (Amazon reviews won’t cut it for me on my water testing anymore).
 
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PH60 Premium Digital Pocket Waterproof pH Meter pH Pen Tester Kit with Replaceable Probe and Backlight-Apera Instruments

The Apera Instruments PH60 Premium Digital Pocket pH Meter / pH Pen Tester is ideal for all kinds of regular aqueous solution's testing, such as hydroponics, aquaculture, pools& spas, water treatment, cooling towers, etc. Can be replaced with ORP probe.
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PC60 Premium Multiparameter (pH/EC/TDS/Salinity/Temperature) Pocket Tester/Meter Kit-Apera Instruments

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@JoyfulNoise has and recommends this.
 
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The PH60 is great. I'm struggling with the darker reddish shades of the pH test and went down the pH meter route for that reason, and don't regret it. Another advantage is that it's not affected by higher FC, so I don't have to worry about not being able to test pH when my FC gets a bit higher.

Important is regular calibration, and to always store it in 3M KCl storage solution. My experience is that calibration is very stable when always doing so.

I just replaced my PH60 (after about 3 years) because it started to take longer and longer for the readings to drift to the final value (they were still accurate). Advantage of the PH60 over the cheaper PH20 is that you can replace just the sensor head. (At least in the US. Proved difficult in Australia, because Apera charges insane amounts for international shipping. I found a replacement sensor on Amazon, but that proved to be a dudd, calibration didn't hold. Didn't bother with weeks worth of fussing with returning it to Amazon US, and bought a full new meter after all from the Aussie distributor, which is working properly now.)

Anyway, the point I wanted to make is, that in the beginning, the new meter (as did the original one three years ago) kept loosing the calibration over a week or so, but after storing it permanently in storage solution, this settled down after a couple of weeks, and the calibration now remains stable for weeks (the dudd didn't stabilise, cal kept drifting). But still important to check the calibration regularly - there are a few threads here where folks got mislead by uncalibrated meters.
 
mgtfp said:
The PH60 is great. I'm struggling with the darker reddish shades of the pH test and went down the pH meter route for that reason, and don't regret it. Another advantage is that it's not affected by higher FC, so I don't have to worry about not being able to test pH when my FC gets a bit higher.

Important is regular calibration, and to always store it in 3M KCl storage solution. My experience is that calibration is very stable when always doing so.

I just replaced my PH60 (after about 3 years) because it started to take longer and longer for the readings to drift to the final value (they were still accurate). Advantage of the PH60 over the cheaper PH20 is that you can replace just the sensor head. (At least in the US. Proved difficult in Australia, because Apera charges insane amounts for international shipping. I found a replacement sensor on Amazon, but that proved to be a dudd, calibration didn't hold. Didn't bother with weeks worth of fussing with returning it to Amazon US, and bought a full new meter after all from the Aussie distributor, which is working properly now.)

Anyway, the point I wanted to make is, that in the beginning, the new meter (as did the original one three years ago) kept loosing the calibration over a week or so, but after storing it permanently in storage solution, this settled down after a couple of weeks, and the calibration now remains stable for weeks (the dudd didn't stabilise, cal kept drifting). But still important to check the calibration regularly - there are a few threads here where folks got mislead by uncalibrated meters.
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Ya kinda made my point for me (fiddling). But as in all things pool, you soak up the advice and then figure out for yourself what works best for you and your pool.
 
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Dirk said:
Ya kinda made my point for me (fiddling). But as in all things pool, you soak up the advice and then figure out for yourself what works best for you and your pool.
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It's all relative. The changeover to the replacement meter was a bit fiddly, but now that it's running smoothly, I don't want to miss it. Just wanted to point out that some care needs to be taken with a meter - blindly trusting a precise looking digital number can be dangerous.

I find the colour comparison more fiddly, but that is my personal view. Luckily there are options to pick the one that suits from.
 
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I have a HM meter, the solutions to drive it cost me more then the meter. The only time I truely trust it is immediately after calibration. The salt meter just keeps on giving, love that thing.
Newdude said:
I didn't like my ability to choose either. I started taking one finger from each hand and blocking off the value above and below the one I wanted to see. I found it was way easier to say yes or no when not being influenced by the other colors.
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What a good idea. Did that this morning and boom, that‘s it. Think I’ll cut cut a window in a piece of white card.
 
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AUSpool said:
What a good idea. Did that this morning and boom, that‘s it. Think I’ll cut cut a window in a piece of white card.
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I do something similar, though I can do it without blocking cells. I don't look up and down the scale for a match, instead I just look at two adjacent cells and ask myself, "Is that more yellow, or more pink?" And depending on the answer I move to the row above or below and ask again. When I can't answer the question, that's the pH. I've gotten good enough at that where I can split the difference. My comparator shows pH in increments of 2, but I can judge pH now in increments of 1. So if the pool water is more pink than one row, but more yellow than the next row, the pH is in between the two.

Also, if you're having trouble with matching, try using four drops instead of five. This made a huge difference for me, because it changes the saturation of the color of the pool water to match that of the colors on the comparator. Much easier to compare the hues when the saturation is the same.

When I read that suggestion here, I was a bit skeptical about skewing the test in that way, so I called Taylor tech support and asked their opinion about that trick. They didn't like it and recommended I stick with five drops. Other than Taylor, the four-drop tip is pretty much endorsed here at TFP (at least by a few of our experts), so I ignored Taylor and I've been using it since, for years now, with no ill effects.

I don't know if altering the saturation in this way would help with Chris' MO, but it wouldn't hurt to try it once or twice.
 
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Dirk said:
Also, if you're having trouble with matching, try using four drops instead of five. This made a huge difference for me, because it changes the saturation of the color of the pool water to match that of the colors on the comparator. Much easier to compare the hues when the saturation is the same.
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I’ve been using 4 drops for a while but mostly because my comparator uses a smaller sample size, prior to that I was always using too much which probably made it harder. I guess I could try 3 to see what that looks like. My comparator goes 8.2, 7.8, 7.6,… where other then reducing TA I think I’ve only ever been below 7.6 maybe once. I’ve never thought of that before but I would guess that most of us are always comparing the colors in the upper end of the range.
 
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I bought a pH60 from Aptera but I stopped using it. Even with proper calibration I found the unit to read on average .2 to .3 higher than a Taylor kit or TF-PRO kit. Plus it seems to take much too long to settle on a number. Then if I remove the probe and put it back in a minute later, the results are different (lower) than they were a minute ago. Just too much inconsistency for me for some reason. Even though I'm color blind, I still prefer the Taylor or TF PRO way to read pH. But to be accurate, I actually test my pH with BOTH Taylor and TF PRO since they use different color-block thingies.
 
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jesse-99 said:
I bought a pH60 from Aptera but I stopped using it. Even with proper calibration I found the unit to read on average .2 to .3 higher than a Taylor kit or TF-PRO kit. Plus it seems to take much too long to settle on a number. Then if I remove the probe and put it back in a minute later, the results are different (lower) than they were a minute ago. Just too much inconsistency for me for some reason. Even though I'm color blind, I still prefer the Taylor or TF PRO way to read pH. But to be accurate, I actually test my pH with BOTH Taylor and TF PRO since they use different color-block thingies.
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That's what kids are for! "Hey, little man, which ones match?"

The Taylor pH test is one of the few I actually like doing. Super fast, super easy, nothing to remember, nothing to go wrong. Probably takes me 20 seconds (not counting collecting the sample). FC another 30, done! I've written before: the goal (for me, anyway) was to see how much I could streamline the process, down to the bare minimum of minutes it takes to test. I figured the less time it took, the more likely I'd do it. Fiddling with a separate gizmo, calibration, cleaning, storing, etc, just doesn't fit that goal (even if it could be shown to be a better way to test pH).

My entire testing setup, and all the automation I use, and all the projects I've shared over the years, how and where I stored chemicals and tools, everything pool... all predicated on the same MO: just how little work I can get away with!
 
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I have partial red-green colorblindness -- I *think* I identify most colors (including reds and greens) easily day to day, but in 7th grade Biology when the teacher briefly showed some of the dot tests, everyone was calling out numbers and I'm like "what the heck are you all seeing?" That was amusing for all, and led to the school nurse bringing up more of them so everyone could be amused by my confusion at what was crystal clear to them. I can't tell if there's a number in most of the ones at Color Blind Test | Test Your Color Vision | Ishihara Test for Color Blindness). Some color schemes people use in presentations are difficult (reds text on blue background for example), and I found the pH test the hardest one to get at first and relied on my wife and kids to confirm.

Anyway, I found that using a "whitescreen" app on my phone right behind the comparator made it a lot easier to consistently compare the colors. I've been meaning to request that as a PoolMath feature. That, along with a realization that it doesn't have to be perfect (it doesn't really matter if I call it exactly right at 7.6 vs 7.7 vs 7.8, because I'm not really doing anything about it until it closes in on 8.0, which I can see pretty easily) made it a lot less stressful.

I know others have more severe inability to distinguish, so using an app to compare is a great idea; I'm going to try it next time.
 
Instead of using an app to measure color, I wonder if using one to rotate the color wheel, so to speak, would be any easier or faster for some. If only certain colors give you trouble, maybe shifting them would allow you to compare. This was just a flick of the hue slider:

1670628934337.png
 
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