Also Known As: Comparator

A photometer test kit is designed to offer more accurate testing of pool water. Because it is digital, a photometer can better assess changes in color of the water or litmus papers, reducing the chance of mistakes due to human error.

In addition, sophisticated photometers can be used with software, allowing pool managers to track water chemistry automatically.

The photometer only assesses color change in the test vial or litmus strip. Therefore, the same steps must be followed for each type of water chemistry test. Then the vial or litmus strip is inserted into the photometer. The color is compared digitally and the measurement is displayed within seconds.

Today, a variety of photometer models are available. Some offer only a few water tests, while others offer a full range. Naturally, this equipment is expensive, ranging from $200 to $1,000. More expensive models feature self-cleaning modes, internet-data tracking and user customization. Of course, staff must be trained to use the equipment properly. False readings are possible if vials are not replaced or the equipment is mishandled. Of course, human error cannot be completely erased. For example, if the reagents are added improperly or if the correct amount of time was not given for the reagents to mix with the pool water, the photometer cannot produce an accurate measurement.