I have been reading about the yellow color and have found that it is aglomeration caused by to high of a particle density of silver made with distilled water. The ionic silver particles start sharing electons and become larger particles. If the color was other than yellow it would indicate the silver has combined with other minerals indicating impure water. I might try some peroxide after doing some reading, to see if it will actually seperate the molecules. At this point I think my colloid is likely the best in the whole world and any messing around will only lower its quality.
I think that yellow color is good because Bob Beck said if the silver particle is to small it will get into areas of the body that will kill off so called benifitial bacteria.
Never the less I have spent yet more cash on a Hanna PWT meter and a lazer because I just have to know exactly what my parts per million are in both my distilled water and my finished Colloid. Lazer and Meter are reasonably priced at this site if anyone interested.