If you're producing greater than 20PPM you MUST add the reducer at the beginning (and the gelatine too if you intend to gel cap the result) AND you must be processing hot (140-150F). Reducers only reduce quickly at higher temp.
One of the advantages of adding the gelatine up front (you must be processing hot - 140-150F) is that there is some data that suggests this creates the smallest silver particles - close to 10nm which is kind of the holy grail particle size.
The trick with higher PPM production is continuous reduction. The solubility limit of silver oxide in water (IS) at room temp (thats 75F!!!) is about 21-22PPM. If you try to create more than this amount of IS before reduction, some won't go into solution and will precipitate out and never be reduced and now you have a mix of IS and Colloidal Silver and thats not good.
At 140-150F, reducers do their job in maybe 10-15 minutes (so a lag of 10-15 minutes from production of dissolved silver oxide to its reduction) so since the solubility limit of silver oxide in water at 140-150F is around 40PPM and since at reasonable current you can't produce that much IS that quickly, your reduction speed will always outpace your IS production speed and the sky is the limit (within reason).
I routinely produce 120PPM this way (gel capped) and it comes out perfect and crystal clear - just kind of reddish/ruby color due to the concentration every time. Dilute a little to 20PPM and the color is perfect but remember, if gel capping, the color will be a little deeper due to the gelatine. If you're reducing using malto instead of karo, again, the color will be a little deeper as well.
I use karo as I'm gel capping immediately. Karo is only good if not gel capping up to 20PPM as its not a very strong stabilizer. Above this (I make 80PPM "naked" occasionally) I use maltodextrin which IS a good stabilizer - have made it up to 120PPM and its stayed good for years. Honestly I've never had any of it ever go bad before I've used it up.
I really can't talk about other reducers. I've had no luck with glucose (dextrose) directly. No matter what I do, I always get a cloudly result. I remember seeing a few other guys on the forum making similar statements. It may have to do with the reduction speed as glucose reduces exceedingly quickly but I've used up all my patience in trying to figure it out and don't want to waste any more silver. I've not tried any others beyond glucose than karo and malto.
I can't say that I've ever had any real plating out of silver on the container. I still do H2O2 clean the containers every 5-10 runs just as a matter of course.
If however, you do notice even mild plating after a run, you must clean that container before the next run because now, that plating acts as a third electrode and that will screw things up and the plating will simply get worse and worse over time and what plates on the inside of the container does not wind up being usable Colloidal Silver (wink).
Also, if you're gel capping you can get a thin deposit on the inside of the container as the stuff cools. When you either move the product to another container or use up what you've made, cleaning off the gelatine film isn't as taxing as it was originally for me.
What I've learned to do is fill the container with plain old tap water (no reason to waste perfectly good distilled, which BTW, isn't exactly cheap to buy). I heat the water in a microwave to just hot enough that the jar becomes difficult to touch/hold without a little pain - thats somewhere around 130-140F - more than hot enough to get the gelatine stuck on the inside of the container to bloom and get soft. I leave it sit like this about 15 minutes, add a couple drops of dishwashing liquid and scrub the inside of the container with a bottle brush - not a lot of work. It all comes off. Rinse the container a few times with tap water, a couple rinses with an ounce or two of distilled to get all the tap water out, cap the jar and put a piece of masking tape on the lid, writing "clean" on it to indicate, its good to go immediately for another run.
I usually save up mason jars and clean about 6 of them in one session - economy of scale basically. I'm done in about half an hour elapsed time.
