I was taught to never feed fresh clones "grow formula", so I always start clones "bloom formula" - most 2 part nutrient formulas the "grow formulas" are too high in (cal/nit) nitrogen and shocks/burns the clones.... my megacrop part A is 15-0-0, I would never use this on my clones my part B is 5-12-26 this is what I use for clones, and Im usually 1.2-1.4 ec (600-700ppm), too much light early clones will pull too much mag, I run lighting at about 40% power and make them beg/pray for it.... (keep light pressure low for the 1st couple weeks - make sure they stay 40-50% wet) Coco isnt the Problem, Ive been in Hydro (dwc/coco) for 15 years now, clones love hydro. keep at it!