I drink a lot of boxed wine and I've saved up nearly 50 of the plastic bag inserts. I want to clean/sanitize them and reuse them for long term emergency water storage, but I'm not sure how to go about this.

How should I treat the water to prevent bacterial growth? I'd prefer it to have as little chemical flavor as possible. It'll be stored in my garage which gets very hot for 6 months out of the year if that matters.

How should I sanitize the bags before I refill them? I was thinking I could fill them with a mixture of bleach and water and let them sit for a night, then rinse until I can't taste the bleach.

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