"By the way, we lived in Sao Paulo, SP, Brazil for 1-1/2 years (can understand more Portuguese than I can speak, though). Is that where you mastered the Portuguese language?"
First off, I have to say that I know no Portuguese at all ... I used FoxLingo to translate that one paragraph as a welcome ... wish I did know it though.
I would not be afraid of adding some minerals right into the water along with a small number of drops of unactivated Miracle-Mineral-Supplement ... there has often been minerals in the greens that I drink too.
Some brands of greens that I like are: Alkalive Green, Jurassic Greens, Green Kamut, Heavenly Greens. These seem to run about $20 or so for 1/2 pound.
Making your own will cost you around $20 per pound. You can also experiment with adding ground herbs as well.
Either way, whether you buy greens or make your own, you can add some peppermint or spearmint for taste, or stevia, and a lemon wedge or lemon juice will help w/taste also.
With regards to the rash, I'm sorry that you are going through that. It does sound like detox to me, and cutting back until it is tolerable is the right way to go. Also, be sure that you drink a lot of water, and get a lot of EFA's.