Opinions about Lamont ColorQ photometer testing

[omoulton]

Thanks for the link Janet. I appreciate it. Otis.

[PoolDoc]

One of the very, very important factors to keep in mind is that the electronic units tend to drift, and need calibration to be reliable.

This is critical in the case of 'wet' sensors, like pH or redox (ORP) electrodes. It's important even in cases of 'color' readers. By contrast, $10 OTO / phenol red kit do NOT have to be calibrated regularly. (However, the color standards in some of the non-brand name units tend to be pretty variable.)

My experience with electronic testers, of many types, has been very consistent when these units are used outside the lab: they don't work well! That's not to say someone could not make a unit that did perform well, over time, and without frequent calibration. But I haven't heard of any such product yet.

Ben

[chem geek]

waterbear can fill in with more details, but reports from users show that there are problems with the CH measurements at higher CH levels, but starts to get thrown off even at 300 ppm. The CYA test can also be flaky. The other tests do better, but as Ben says it depends calibration, especially for pH. The chlorine test is DPD so still gets bleached out at higher chlorine levels.