A colloid is a substance in which microscopically dispersed insoluble particles are suspended throughout another substance. Sometimes the dispersed substance alone is called the colloid;[1] the term colloidal suspension refers unambiguously to the overall mixture (although a narrower sense of the word suspension is contradistinguished from colloids by larger particle size). Unlike a solution, whose solute and solvent constitute only one phase, a colloid has a dispersed phase (the suspended particles) and a continuous phase (the medium of suspension). To qualify as a colloid, the mixture must be one that does not settle or would take a very long time to settle appreciably.
If you have silver ions in water that is not a colloid but a solution. If you have molecular silver (silver sulphide, chloride) those are insoluble and could be suspended in water as a colloid. Using electrolysis to drive Ag ions into the water creates a solution.