the silver is ionic, not colloidal. That milky-white precipitate is from the reaction between the chloride in the tap water and the silver ions, forming silver chloride. that silver will do the same thing when it mixes with the HCl in the stomach.
I'm not a big fan of Colloidal Silver , but I respect others' choice. True Colloidal Silver is stable for about 8 hours, 12 at best, unless steps are taken to control the zeta potential of the suspension.