Once clones are rooted, week 1, 1/4 strength, week 2, half strength, week 3, 3/4 strength, week 4 full strength. In DWC I rarely went over EC of 1.2. SInce the roots are almost permanently submerged in solution, they dont need a high EC. The curling you saw is nute burn. Also, I always ph'd to 5.5 and allowed this to drift up as high as 5.9 to give good coverage of all nutrient absorbsion levels. 1 drop superthrive per 4l of solution, EC of 500, ph in the 5.5/5.9 range. Do not trim damaged leaves, they may recover a little and in the meantime they are acting as solar panels absorbing light and photosynthesising. W