Automatic Pool Water Tester

[BelSplash]

The issue is price and calibration. Sorry, I should have qualified the answer better. I am talking about a proper lab-grade photometer, not a domestic item. These require annual calibration and would cost about $1500.00

No, they don't. If they require calibration they're already broken and should've been checked earlier. There can be a degradation of the light source, optical filter or sensor, but that would lead to a reduction of sensitivity, not inaccurate readings (ie high one time, low the next).

To TS, I use a Lovibond Scuba II to good effect, but the sample prep requires some extra knowledge and adaptation of the protocol due to TFP methods and values.

 

[Bperry]

If you do not have visual issues preventing the use of a colourmetric comparator, then they are the way to go.

The detail that seemed to get overlooked is that TFP doesn’t recommend using kits with a color comparator and so they definitely aren’t the way to go.That’s the whole point of using the Taylor kit. None of the Taylor tests (except for pH) use a color comparator.

And the one test that does use a color comparator, @Newdude showed how to get good results with it it above. If the sample looks some shade of orange, the pH is low. If the sample is purple, add a little acid. That’s it.

 

[DavidLast]

The detail that seemed to get overlooked is that TFP doesn’t recommend using kits with a color comparator and so they definitely aren’t the way to go.That’s the whole point of using the Taylor kit. None of the Taylor tests (except for pH) use a color comparator.

And the one test that does use a color comparator, @Newdude showed how to get good results with it it above. If the sample looks some shade of orange, the pH is low. If the sample is purple, add a little acid. That’s it.

Sorry in the Australian industry any test kit that uses a block for colour comparison of the DPD result, pH result and titration is a colourmetric comparator. This includes the Taylor kit which we used to use 30 or so years ago.

 

[Bperry]

Sorry in the Australian industry any test kit that uses a block for colour comparison of the DPD result, pH result and titration is a colourmetric comparator. This includes the Taylor kit which we used to use 30 or so years ago.

Then that would not be the test method TFP recommends. FAS-DPD is what TFP promotes because the yellow DPD/OTO comparator is pretty vague.

Maybe its a language thing? Color comparator means that colors are being “compared”. An example is test strips where you place the paper strips next to the bottle and compare a variety of colors to estimate which one is closest to your sample. Another example is the yellow OTO chlorine test where you compare shades of yellow. These are really hard to use and are sometimes what people think ALL testing is like because it’s been done like that for 30+ years. But that’s not the case with the TF-100 or the K2006C.

The TF-100 doesn’t compare any colors (except pH) The sample starts out as pink and changes to clear (in the case of FAS-DPD). There are no comparisons to be done, except for the pH, which is the only test where there’s any comparison needed.

 

[DavidLast]

The FAS dpd method is not standard here.

Any colour comparing system, including drops to titrate to an endpoint colour change, is a comparison of colour.

 

[Newdude]

Any colour comparing system, including drops to titrate to an endpoint colour change, is a comparison of colour.

Technically yes as you are comparing pink to clear, or green to red, etc. But the Taylor drop tests aren't looking for shades of a color which befuddle us all, especially those who are colorblind. Instead it's easy to tell the Taylor colors changed, even if you don't know what color they are. Take salt for example. It's a drastic change from milky yellow to brick red. You can call both sides of the test whatever you like, but you saw a big change to let you know it was over.

The same goes for all of them, with the exception of PH, where anything in range is a similar shade of pink. But that's also its work around, because anything in range (pH in the 7s) is equally OK for most. They can tell on the block when it's low or high as those are different colors than the 7s.

 

[Bperry]

The FAS dpd method is not standard here.

Any colour comparing system, including drops to titrate to an endpoint colour change, is a comparison of colour.

I can see why the term comparator might just be a point of language differences, so no worries.

But there’s a very real difference in ease of use between directly comparing 5 shades of “green” against a standard and being able to see that a color changed from red to green. The first example can be hard for lots of people but the second example is much easier for most and that’s the whole reason TFP recommends testing that uses the second style and specifically rejects trusting the first style.

 

[mgtfp]

The FAS dpd method is not standard here.

Any colour comparing system, including drops to titrate to an endpoint colour change, is a comparison of colour.

I don't think FAS DPD is standard in the US either. But it's what's required to apply the TFP method.

In Australia, Clear Choice Labs in Brisbane is selling FAS DPD kits.

The difference with a titration test is that you don't need a colour comparator. You just make a black-and-white type comparison, not a colour shade comparison that requires a subjective comparison with shades on a scale.

In the end it's splitting peas whether you only call a test that requires a comparator block a comparator test, or any test that requires some sort of colour comparison. I think we all know what it's about.

 

[AUSpool]

The FAS dpd method is not standard here.

Any colour comparing system, including drops to titrate to an endpoint colour change, is a comparison of colour.

Titration chemistry and colourmetric tests are different. A $1500 photo meter is a toy, they may be used for field testing but lab grade photo meters are 10x that and then some. Plus a good lab grade photo meter is used by trained professionals using certified standards.

 

[duraleigh]

I don't think FAS DPD is standard in the US either. But it's what's required to apply the TFP method.

In Australia, Clear Choice Labs in Brisbane is selling FAS DPD kits.

That should be the pertinent takeaway, TFP methods require the use of FAS/DPD to test chlorine

 

[AUSpool]

That should be the pertinent takeaway, TFP methods require the use of FAS/DPD to test chlorine

A titration kit for FC, inexpensive, accurate, repeatable. Doesn’t bleach out over 10ppm. Can test as high as you like. The best you can get for home use.