You said it for us David. 
I'm a 'newbie' here myself, and I don't agree with the half a ppm theory, but I 
chose not to dwell on it.
Positive Thinking does wonders for him, more so then me, it seems. I feel more 
ppm is better, even though I don't go any higher then twenty, and even then, I 
add water to make it somewhat less.
I have hopes that other new people won't just take the word of one person, 
before limiting themselves to something so small a percentage. But to each 
their own. Personal experience is all the best advice I can offer. 
~Just my thoughts~

Kenneth

Karen is Healthy, Wealthy, and Wise