Hot answers tagged water-purification
Is this rust by chance? If so, let it dry and it'll be powdery at the bottom. Run your finger on the surface and some will come off on your finger. If it's rust, you may be able to get it clean with some steel wool. Just make sure to keep it dry after use from then on. SmemSeger could be correct and that it's mineral deposits. I usually find those to be ...
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