Yeah Horseman,

Well water is fine, and under 150ppm is excellent quaility usually.(As long as it is not run thru a "sofener" system) Consider you probably have some trace minerals already there, and typical wells tend to have some calcium already; but cal/mag is good to use anyway. The only time I don't recomend the use of cal/mag, even with RO water, is if you use Pro-Mix and containers. Pro-Mix contains dolomite lime, whichs gives up calcium and magnesium, so it is already in the mix. (reason glass-house operators use it)

Not sure you should take anything as gospel, even the gospels'.

BTW: when I was younger I was "large", now I'm just flacid.