I am betting, that HYDRO has more yields + you get more grows in a year.. Thus more weed, thus more weed to sell, thus more money on the investment.. I would realyl like to look into HYDRO, but Its a steep start up cost for me, All I wanted to do was grow a couple of ounces so I could stop smoking that B/S that my peeps in the hood were selling me.. So we are talking 4-5 plants every 3-4 monts, so maybe I can squeze in more with more lights or SOG.. but for me its just a matter of some nice herb to smoke.. I wish there was a basic HYDRO set up for one plant, I am sure there is.. I may try that one day.. Fun to learn.. Someome once told me you get could 4 oz from one plant doing HYDRO, so that would be worth it.. if it were true?