1. PPM is measured by a TDS meter. In measuring CS, its only good to get an initial reading because one is supposed to start with zero. Once CS is made, we go by color to determine the strength or with sp2 - go by amount of time processed. the water will have a metal taste.
2. 10 ppm, you can have as much as you like if you are sick. I have 20ml of 10ppm every day. It’s great for ear infections and throat infections. Ppm meters are not that accurate but close to. You can buy them online. If you make your colloidal silver you can shine a pen laser through it and you can actually see the silver in the water. Don’t use tap water. The best water to use is distilled water.
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