First time auto, & first time in coco

9-9&9-11 Seems to be doing good and looking healthy, but still seems to be taking her time growing out. I've been feeding her @900ppm(200ppm start) at 5.8ph around 1-1.5liters of water. 9-13 Looks to have decided to grow a bit finally and looks healthy. Eventually I'm going to switch to RO water, within the next week. 9-16 Checked her in the normal light and she's looking pretty dark green, emerald green even. So I flushed her and the other 2. In my research I've read that checking the runoff ppm/ex is pretty pointless and others say to keep an eye on it and if it gets to be really high you'll run into problems. I checked it yesterday and it was around 4k ppms, wtf! That was also one of the reasons for flushing.