im definately staying soiless, first of all.....thanx ganjarob. i appreciate the info. ill do as you say and add some grow (N). i thought that it was best to eliminate the N considering that micro has alot. so the GH nute calculater must be close with ppm for waste to drain (850), though their reciculating calculation seems high at 1400ppm max bloom. i figured that when the plant started to yellow i needed to raise the ppm. the problem ive had in the past is that the leaf tips seem to brown even at relatively low ppm (600-700). i used to do recirculating and then watch the ppm as the reservior drained . if it went up i decreased the nutes if it went down i increased . but i never got past 700-800ppm that way. does that sound normal. thats less than the drain to waste levels. thats why i went to drain to waste but its my first time so i need nute strength/ratio help. wha t do you think of can grow it's answer of going to 1800ppm?? thanx for helping too CGI, but these answers are conflicting somewhat, just trying to get the right advise