sodium thiosulfate

[michimichi]

is it acceptable not to use sodium thiosulfate on water sampling bottles prior to sterilization and sampling?

[JorgeLobo]

Thio is used to neutralize residual hypochlorite/chloramine that may limit microbial signal, esp. for coliform testing. Suppose nonchlorinated well water might not require it, but it is standard procedure. suggest you read appropriate chapter in Standard Methods for Testing Water and Wastewater.