Disaster after holidays

Hi everyone, Im just back from a 5 day trip to Amsterdam. First thing i did when I got in the door was check on my baby, now the plant hasn't been water since the day I left, (I usually water every 2-3 days, 15 liter smart pot) so i wasn't expecting it to look to great, maybe a few droopy leaves but it has a new problem for me. Pic below. Google wasn't much use to me, it is giving different answers depending which forum you visit. Anyone able to shed some light on this for me.Its an advanced seeds ice kush, 250w hps, nutes are a home made comfrey tea for nitrogen and a generic 13-14 bloom mix. I have very basic pH testing strips and they say its pH 7





sorry for the shit pic, phone and what not, if you cant make it out im getting these brown spots forming in along the main vein on the leaves, which seems to then spread to all the leaf.

p.s. i didn't have this problem before i left, it seems to have manifested while i was away.

 

the light schedule is,
Lights on at 10pm off at 3.30am on at 4am and then off at 10am. Temps are crazy high 36-40'c but i have had this problem all throughout this grow, need to buy another more powerfull extractor fan.


I may look into buying one of them, seems it could be usefull

 

@capt.murphy


I read an article about mid day depression in plants, in short plants can only photosynthisize for so long and then need rest, so i thought id give it a try but i doubt it will make much difference this grow with what problems i am having

 

@naturalmistik my 250watter is around 15inches from the tallest cola, i also have a pain of glass inbetween the light and plants.


I no temps are way to high, i was using 1 pc fan for extraction amd 1 for intake but they just wernt cutting it anymore. I then upgraded to a 4" cheapy fan that also isnt cuttingthe mustard so for the next grow i will buy a 5" inline fan.


I cant add an oscillating fan i dont have the room. I have a pc fan to keep air moving around the plant.