~ I could guese at what exactly the problem is but..... it seems you are getting good advice, there is always trial and error, one thing I can think of that no one seems to have touched on (i only skimmed through replys) Is those charts are usually geared towards high lumen (footcandle) gardens. Lets say 9000 lumens to the tops, 10,000 being ideal or at least 1000 watt HPS lights. I you are using a 4oo or LED, Or whatever you may want to cut your food back whatever percentage your light is less than 1ooow. So a 400 watt hps would be 40% the food, or a 600 watt, 60% the food. This is NOT accurate mind you 600 can be placed closer , and yadda yadda, but plants really go through food in high light situations, and may only sip in low. All im trying to say is the chart is only an estimate, not a rule. I have heard great things about drain to waste rockwool, I have never tried it, Peace.