The question naturally becomes, “What are the differences between the water quality testing methods?”
- Test Strips: A test strip manufacturer such as Industrial Test Systems, Inc. will try to sell you on the speed, portability, and cost-effectiveness of their water testing strips.
- Color Comparators: Manufacturers such as Lamotte, Inc. will try to sell you on the convenience and improved accuracy associated with having multiple colors located right next to the test sample.
- Colorimeters: Electronic colorimeter manufacturers such as Industrial Test Systems, Inc. (note: This company apparently knows more than one way to skin a cat, er, test drinking water.) will brag about the convenience of not having to worry about differentiating between color blocks or standards, the convenience of a digital read out, and the accuracy of this method of water testing because it removes the element of human interpretation.
So… Which type of drinking water testing method does the best job? Depends on who you ask! Each method has distinct advantages and definite advantages.
- Test strips offer fast, inexpensive on-the-spot results w/o the inconvenience of the wet chemicals and powders often found in color comparator sets and have a lower per test cost than using a colorimeter. Test strips also boast a pretty good shelf-life. They typically do not, however, yield the same amount of accuracy as other drinking water testing methods.
- Color comparators give pretty decent accuracy when used properly and with fresh liquid, tablet and powdered reagents. Cost for reagent refills runs pretty inexpensive for basic tests but can get pricey when testing for more advanced water quality parameters such as lead, copper and iron.
- Electronic olorimeters have a high start-up cost compared to the other two methods but they completely remove subjectivity from the testing process and so therefore a quality colorimeter will almost always yield more accurate and more consistent results.
So…. Which test method will work best for you?
- Need a fast, easy-to-use method for general screening purposes? Go with test strips.
- Need a drinking water test kit with a little more accuracy and can handle the mixing of powders and crushing of tablets? Go with a color comparator.
- Need reliable results each and every time you test and don’t mind crushing tablets, mixing powders and spending a little bit of money up front on a decent water quality testing instrument? Go with an electronic colorimter.