![How to get this black stuff off my rubber bottle seal? I've tried soaking it in hot water and using a knife to try and scrape it off, but nothing's worked : How to get this black stuff off my rubber bottle seal? I've tried soaking it in hot water and using a knife to try and scrape it off, but nothing's worked :](https://preview.redd.it/how-to-get-this-black-stuff-off-my-rubber-bottle-seal-ive-v0-5rkntbesn8na1.jpg?auto=webp&s=798cbf7efe84d7340594a63fb9eee66e76c30174)
How to get this black stuff off my rubber bottle seal? I've tried soaking it in hot water and using a knife to try and scrape it off, but nothing's worked :
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ROYAL STUFF Quality Heavy Copper Water Bottle | 1000 ML | 100% Leak Proof | Tamba Bottle | Gym Bottle | Yoga Bottle | Home | Kitchen | Hiking | Treking Bottle | Travel Bottle (Pack of 1) : Amazon.in: Home & Kitchen
![Any ideas how to clean brown stuff off the inside of my bottles? I have found that shaking with salt & water can get it off a little, but curious if anyone Any ideas how to clean brown stuff off the inside of my bottles? I have found that shaking with salt & water can get it off a little, but curious if anyone](https://preview.redd.it/any-ideas-how-to-clean-brown-stuff-off-the-inside-of-my-v0-v3an36azhwv81.jpg?width=640&crop=smart&auto=webp&s=252b8b9584d97387f3c362bb175655492ba67923)