I only just noticed this post you made about buying ineffective CS.
Years before I started making CS, I had a hunch to be wary of somebody sending me something that may amount to nothing less than plain clear water. Anyone who buys CS should test the contents by placing a small quantity in a glass & dropping a few grains of salt into it, just a pinch of salt is enough. Wait a few minutes to see if a whitish cloudy appearance shows up, if it does, you're good to go, otherwise not. I use non-iodide salt to test every batch I make because I don't know if Iodine in salt will affect the outcome or not, maybe I should try it sometime.
One thing about the salt test though, if silver ions in the CS is much under 5 ppm you may not see much cloudiness, or maybe none at all if the ppm of silver ions is really, really low, in which case your CS is probably pretty useless for anything, be it for ions or for solid non-ionic nano-particles. The salt test is not indicative of the presence of non-ionic colloids (solid nano-particles of silver), only for ionic colloids.