Hi Gerard,
I’ve read similar things on Reddit. On the One Step website (a sodium percarbonate-based cleanser) it says: “CIP [Clean In Place] Cleaning: Use 0.5 for daily treatment of minimally soiled vessels and equipment, but for heavily soiled vessels such as fermenters, 3 oz is recommended. Heat the solution to **120 – 180 F** and circulate for 30 minutes. Follow with a potable water rinse.”
As for shelf life / effectiveness of keeping a batch on hand, given the ease of use, I just mix up the cleaning solution as needed because what I’ve read on various message boards has been highly variable.
https://www.ecologiccleansers.com/wp-content/uploads/2015/07/OneStep_05-15.pdf
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