See newbies. Auntie Clara does use different water discounts to create halos. I was referring to trying to make a stripe of different color, say green, on a circle, say purple. I was brainstorming, but what I was thinking is totally different than claras. She used 1:1.5 and 1:2 or something higher maybe, as water discounts to see those halos. If you back up to my link on this thread, several pages back, I linked to the exact blog post you're thinking of and newbie showed just now. You can Google auntie Clara crop circles and reach the page as well.
I now, from her experiments, do a 40% lye discount or 1:1.5 lye to water and no longer have to worry about ash. Yea!