Review on 🔬 Hanna Instruments HI721 Portable Colorimeter by Carl Morgan

We are having problems with iron from our well, both FE+2 and FE+3, and iron bacteria. So not only do I have to chlorinate the well twice a year, I also have to constantly check that the iron filter is doing its job. I have previously used a test kit that uses a similar reagent that turns the sample orange. They then compare it to a color chart. The problem is that there were only 5 reference colors in the kit for 0.3, 0.5, 1, 3 and 5ppm. It's very hard to see exactly what you have, it's enough for a reach. But hardly. I used the Hanna tester for the first time over the weekend and it read 0.15ppm at home. I used my other test as a comparison, I could see there was a slight orange cast and on the chart the best I could tell was that it was less than 0.3 - maybe halfway between no color ( 0) and shading 0.3. That was pretty cool. I tested my raw well water with Hanna and it showed 2.8ppm, when I used the old Mark 1 eyeball test I could only see it was somewhere around 3ppm which could be more or less dependent on the lighting. Within the limits of the old test set, I could at least tell they were in the same range. Maybe the actual accuracy isn't as accurate as Hanna tells me, but now I have an actual number that isn't as subjective compared to manually evaluating the result. I like it!