Ah, yet again the question is asked....

It's very simple B-LO.... Water source is preference.... Some people live in an area where tap works for them....some don't....

Like WashWonder mentioned, if using RO or Distilled water, micro-nutes will have to be introduced to give the plants the needed trace minerals.... A bottle of Cal-Mag and Liquid Karma will take care of that....

The reason I don't like using tap is because I like to know where all the ppm's come from....and tap water is usually laced with chemicals that kill bacteria....and I like my beneficial bacteria alive and well in my soil, so....RO for me....

CGI::::::