FountSILVER Water Booster concentrated Silver AgNP fountain water treatment solution is non-toxic (see Safety Data Sheet) and consists of concentrated 99.99+% pure Silver as 100% bioavailable Silver nanoparticles (AgNPs) colloidally suspended and dispersed in pure deionized water. FountSILVER is an odorless, very dark blackish brown colored liquid when seen from the front and has an orange color when backlit, but will not change the color of the water in your fountain or other water feature and will not stain your fountain or other water feature; it is not irritating and not photosensitive. Please see more details listed below which address the history, solution, purity, safety, effectiveness and trust related to FountSILVER. This is 250 mL (8.45 Fl Oz) of SILVER nanoparticles in an amber BPA-free plastic bottle. FountSILVER does not require refrigeration after opening and has an infinite shelf life if stored at room temperature.