i have a 6" fan sucking in air from outside the house onto the bulb, a 4" carbon filter taking out and an oscillatin fan blowing at light as well temps are from 25 - 30.c depending on weather. grow in rockwool ph is done wit an aquarium set and colour is light green which is supposed to be 6.. hardly given any nutes gave 1ml per litre twice during veg and wen i switched i giv 2ml veg and 1 bloom per litre on the advice of sum 1 on here, hope that was right? last watering was jus water. gunna giv 2mlbloom per liter every other watering ffor flowering . i know its a gutter jus as they do their stretch they gt stunted grrr sure they will recover though hopefully nxt set will be ok. why u think they so yellow though m8, heat as well?
hi again lol last couple of days my babys have bushed out and stretched nicely ready 4 flower(bin 7 dys 12/12) all of a sudden my top leaves have come out REALLY yellow and have a funky twist with weird brown spots on them. also they look like they dont want to open out fully. check pics out!! obvious thought light too close? its a 600w hps at bout 500mm away with cooling fan straight onto bulb . wat u lot think ? 
i have moved light away now just in case
