I agree with Griz. He has done the research. Stirring with Aeration is best by being an advantage in creating nascent oxygen (which has no deleterious affect on the water, as some have been fooled by special interests into believing, and a decided deleterious effect on pathogens), and only negated from past, false, undocumented, advertising (and those with personal opinions too strong to be influenced by science).
Research has shown that Polarity reversal is unneeded if we are concerned about oxide particulate entering the mix in anything other than viewed flakes. There is no major creation and or release of oxides of silver problem in any case. Cleaning the silver is certainly no big deal.
Its the size of the silver ion atoms groupings (particles) that are the most important thing to consider when buying a generator or making one (why not, as BS shares, DIY, since the info is so clear and available now), and the determining factor in particle size is the very low current and small ratio of voltage to current used (according to the research and TENS photos)(the whole difficulty in starting electrolysis in distilled water at low voltage is another topic not often considered or well understood, even by techs, since it's only a situation, as far as I'm aware of, in the LVDC CS generation).
"The constant aeration of the water also prevents excessive electrolysis from building up in the solution. This is important, because when using a standard colloidal silver generator, the electrical conductivity of the entire colloidal silver solution is increased dramatically as more silver particles enter the water. In turn, this increased electrical conductivity causes additional silver particles to be drawn from the positive silver electrode at a faster rate and at a significantly larger size. (By keeping) the entire colloidal silver solution super-aerated during the colloidal-silver making process, the buildup of excessive electrical conductivity is dramatically mitigated, because air is one of nature's least conductive elements. Super-aerating the water prevents excessive electrical conductivity from building up, which in turn prevents additional silver particles from being drawn from the positive silver electrode at an excessively fast rate that results in excessively large particles". http://www.thesilveredge.com/aboutmicro.shtml#.WAOeh9LrtT0