Hey there ! To solve your heat problem, buy a cooltube. For autoflow you can switch directly to HPS, 600 should be enough for 9 plants (I'm currently using 400HPS for 6). I use to buy soil so can't really help you with your mix. Don't be afraid of pushing them a bit a this point, you should've started nutes at day 7 with 1/4 the schedule, just to train them receiving nutes.
Seems like your light is too far from your plants, you stretched them a looooot, way too much.
Seems like your light is too far from your plants, you stretched them a looooot, way too much.
