Drop Based Borate Test Kit.

[giroup01]

But don’t forget, the Proteam test requires that you determine a color change in 20 mL of water.

The color change is much easier to determine in our test because you are looking down from the top into a more or less narrow cell containing 44 mL of water. And the cell has a white dot at the bottom that increases contrast and facilitates viewing. Because the viewpath is longer this increases the color intensity and makes the color change much easier to spot.

Similarly, in Taylor’s phosphate test, you are required to look down from the top of a (5 mL) long and narrow test cell to determine the sample color. One would be hard pressed to determine the color of that 5 mL sample if it was, say, in a beaker.

44 mL of Taylor Standard Solution R-7062 (pH 7.6 Standard Solution) with BTB produces the same hue as the endpoint obtained (and shown) in our instructions.

[rcy100]

I've done this test a few times now on my pool and all I can say is I find it quite easy (the speed stir makes it even easier) and the colour change (for me anyway) was easily discernable. I've never tried borate strips, so I can't compare, but if the borate strips are anything like the standard strips (i.e. hard to read) I'll gladly keep this drop based test.

However, as everyone is quick to point out, absolute accuracy is not essential with borates, so whatever floats your boat when it comes to testing is good.

[waterbear]

The LaMotte borate strips are very easy to read with distinctive color changes. The Aquachek strips are next to impossible to read. The Proteam kit is very tricky to do right. I am going to try the test with the 44 ml sample and the acid and base demand reagents and see how it goes. (I already have quite a bit of mannitol and bromthymol blue on hand since I have more than one Proteam borate test kit.)
However, like I said before, this particular test is usually done with a pH meter since it is very easy to overshoot the step when you just neutralize the acid used to get rid of bicarbonates in the water (and the sample is usually heated at that point to make sure all the CO2 is gone) so you are only titrating boron and not carbonic acid. Proteam took a novel approach in designing this test kit (and I am sure John Garvin, who holds the orginal patents on borates in pool, had a hand in it).

The trick to see the titrations precision is how repeatable are the results on the same sample. I have not found the borate titration as repeatable as the LaMotte strips.

[chem geek]

I received the Piscines Apollo borates test and tried it out in my pool today. I can see what waterbear is talking about with regard to not having the same sort of "keep adding drops until there is no color change, then do not count the last drop" problem, but I tried the test going past the first transition to blue in several different amounts and basically so long as you end up at the same transition point in the first part of the test (before adding the powder) and the last part of the test, then the results are very consistent. That is, if you stop adding drops when the sample "first turns blue" as indicated in the instructions, then you get the same result as when you go past that by some fixed number of drops to get, say, a deeper blue, so long as you do the same thing in both parts of the test. It does seem to me to be repeatable to within one drop as advertised since I did the test 5 times and got the same result (within one drop) -- again, so long as I stopped at the same point in both parts of the test. The transition to blue is like most other dye tests, not completely definitive in one drop, but it does seem pretty clear within two so should be easy enough to pick one's transition point to be consistent for the second part of the test (i.e. if you go further in the first part to a darker more distinct blue, just be sure to do that later as well).