@Sherlock, these folks are trying to help you avoid what so many on this site have experienced.
I think you may have had some bad water test experience. Its not as hard or subjective as it sounds with the kit TFP uses. For reference, heres the Leslies test tolerance specification attached for some data.
Take chlorine as an example: It says it can read a maximum of 15ppm, and at any value over 1.2ppm, the accuracy is +\- 25%. If my FC reads 4ppm, it could actually be 3ppm or 5ppm. Thats a huge difference that grows as chlorine requirements get higher. And thats with a perfectly calibrated machine, operated by a competant employee, and properly cleaned from the previous test.
The accuracy of the Taylor tests are all +\- 1 drop and the chlorine test is accurate to +\- 0.2ppm all the way up to 50ppm. So its quite easy to say that the one test kit is more accurate than Leslies testing.
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