My general rule of thumb is to watch for precipitation of silver particles in your storage bottle. If the silver particles are beginning to fall out of suspension and coat the sides or bottom of the glass, then it is time to make a fresh batch. Otherwise, if no precipitation, it should be as good to use as freshly made colloidal silver.
There are any number of reasons for precipitation of silver particles. For example, if your colloidal silver generator is making overly large particles, you will often see premature precipation of the silver particles. Also the use of salt or baking soda or other additives to boost the speed of the colloidal silver-making process will add to the overall size and weight of the silver particles (due to agglomeration of the particles into larger particle clusters), and will ultimately cause them to precipitate (fall out of suspension in the solution) prematurely.
The new Micro-Particle Colloidal Silver Generator produces silver particles so small there is no precipiation whatsoever. Ihave stored a quart of micro-particle colloidal silver in my kitchen cabinet for three years now, and there is still zero precipitation of the silver particles, meaning it is still as fresh (and potent) as the day I made it.
Last weekend my wife and I attended the Mega Book Marketing Conference in Los Angeles with best-selling author Mark Victor Hansen, and I began to come down with the sniffles. Mark's conferences are enlightening but gruelling for an old guy like me. They generally run from 9am to 9pm every day for three days, at breakneck speed and intensity. And I realized that between the travel to get there and the long hours at the conference I was growing not only exhausted but getting congested as well. I also realized that in my haste to leave for the conference I had failed to bring any fresh colloidal silver, and that the only colloidal silver I had was in an old glass bottle wiith a plastic pump spray lid, that had been in my travel shaving kit for the past six months. I was concerned that the colloidal silver would not help, due to the poor storage conditions and the age of the batch. But when I checked it there was no precipitation of the silver particles whatsoever, and it worked like a charm. I drank several ounces, put several drops in each eye and ear at bedime (many infections enter the body at the eyes and ears) and used the spray pump to spray some colloidal silver into my throat while inhaling deeply to get it down into my lungs (kinda like a makeshift nebulizer).
By the next day I was much better and was able to continue through the conference with no more sniffles or congestion. That's the beauty of owning a colloidal silver generator that produces true silver micro-particles. The "freshness" issue is practically non-existent because of the remarkable stability of the colloidal silver produced by the generator.