Fastbuds first ever grow

So this is my very first grow and to say I’m excited is an understatement lol After much research I decided to grow 1x FastBuds Pineapple Express 2x Positronics Jack Diesel All 3 of my girls are Auto’s as I thought this would make it a bit easier as I’m a newbie! I’m growing in a Black Orchid grow tent with a 6” exhaust and carbon filter, 6” inlet fan, 2 small clip on fans and 2x 350 Mars LED lights. I’m using 10l smart grow bags filled with a 70/30 mix of coco coir and perlite. I keep the PH between 5.5 and 6.5 and am currently on wk 2 of flora’s nutes schedule. Have just started to grasp the feeding/watering situation, last week I stupidly mixed up a wk 2 solution of nutes and the first true set of leaves at the bottom have paid the price! I think I over watered them slightly as well. I let them dry out for a couple of days then just fed plain PH water the next few times. They had a very weak mix of nutes Thursday and I will give them the rest tomorrow. My PPM reading was 868 is this right? Would really appreciate your pearls of wisdom as I am a newbie at growing my own medicine!! Can’t wait to smoke it. 😁