Pokemon Center Japan silicone molds

These are ice molds but I used tap water to make ice and they got hard water stains, hard to get rid of. I tried using Isopropyl alc*h*l and It didn't work.I think they could be repurposed to use with resin. If you can safely remove the stains it could be used for ice or jello.I read you can use vinegar to remove the stains but I didn't try in fear of not working and leaving bad smell.Please only buy if you are okay with the hard water stains. flawless for everyday use. supreme materials and excellent craftsmanship ensure long-lasting durability.