What is added to a bacti bottle to remove chlorine?

Sodium thiosulfate is commonly used to neutralize chlorine in various laboratory applications, including the preparation of samples for microbiological analysis. When chlorine is present, it can inhibit the growth of microorganisms, leading to inaccurate test results. By adding sodium thiosulfate to a bacti bottle, chlorine is effectively removed through a chemical reaction, allowing microorganisms present in the sample to thrive and be accurately assessed.

The other substances listed do not serve the same purpose as sodium thiosulfate. Potassium permanganate, for instance, is an oxidizing agent that can actually produce chlorine-related reactions rather than neutralizing chlorine. Sodium bicarbonate and calcium carbonate are both buffering agents and do not react with chlorine in a way that would effectively remove it from a sample, thus failing to prevent any inhibitory effects on microbial growth.