Hello! I am growing 4 plants in one dwc and plants...

i had few grow whit cfl and 3 to 4 inch is fine but it depend on strain or intensity of cfl (150) for veg 6400 lumen or for budding 2700 and LED (630W DE CMH) 24-26″ (60-66cm) or more and if you follow instruction on the bottle for nutriment it would be ok too that brown might be water that dry on leaf too if you spray them or nitrogen deficiency i can give you a recipe if you need