Important Notice: Our web hosting provider recently started charging us for additional visits, which was unexpected. In response, we're seeking donations. Depending on the situation, we may explore different monetization options for our Community and Expert Contributors. It's crucial to provide more returns for their expertise and offer more Expert Validated Answers or AI Validated Answers. Learn more about our hosting issue here.
The “white stuff” found in some coliform sampling bottles is sodium thiosulfate, a chlorine neutralizing chemical that inactivates chlorine so that a valid total coliform bacteria test can be obtained. The sodium thiosulfate should NOT be rinsed from the bottle even if there is no chlorine residual in the system.
