Ok so I went down and picked some up. He says they were back up water for times when the water system at his work (a Pharma) was switching filtration systems. The guy seemed legit, I told him what I was going to use them for and he said it should be no problem and that they have only ever had purified water in them. I'm just a little worried, they look quite official for bottle water. But I'm starting to clean them out and then sanitize them and I think I'll use on tomorrow as a primary.
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