The Sutro Test Cartridge has small mixing balls that are used to make sure the reagent and sample water are well mixed. If you're interested in how the Sutro monitor measures chemistry, you can check out this article.
The Sutro Test Cartridge has small mixing balls that are used to make sure the reagent and sample water are well mixed. If you're interested in how the Sutro monitor measures chemistry, you can check out this article.