Is this a heat issue ?

This is my first grow and everything seemed to be going well until flowering.

They vegged nicely under a 300W CFL, but now it's come to flowering I have them under a 600W HPS and the leaves appear to be curling and on one plant have actually burned a little ?

Is this a heat issue ?

Hopefully these pics will load up....

Strain is White Rhino and they are in a 1.2x1.2x2m tent. I have added the extraction system which is also seen in the pics and a small fan on low blow so not to blow the plants all over the place but it still seems to hot. I think the one that is worst off dried out a fair bit with the heat and had little to no water.

I was thinking about a cooltube but apparently from reading they are not so good and right now the near £200 neaded for the Magnum reflector plus another extraction system is beyond my finances.

So anyway, first things first.... Are my ssumptions correct about the heat ? I have no themometor yet, something I will pick up today

Thanks for any advice

hmmmmmmmmmmmmm. It does look like heat stress but that light is pretty far away. You would have to be REALLY hot to cause this.

Looks like heat stress to me, how far above those plants is that light exactly.

Light is right at the top of the tent, perhaps a metre or more. It was slightly lower on the plant that looks the worst as it was the only one in the tent at the time. It looked fine after the first day, but the second day it looked as it does now and that is when I raised the light right to the top of the tent and added the 2nd plant. 2nd plant has been in the tent for 1 day on a 12/12 cycle but looks to be curling along the edges of the leaves to... I know this one has not dried out and has been kept well watered.

Tent is certainly warm but it's not THAT warm ?

How do you think the worst plant will fair ? She's not to bad is she ?

looks like heat stress. good call. It's just that time of year? hard to keep optimum conditions without ac

the powerplant aircooled hoods willl be perfect for that tent! i use one and love it, heres a link http://www.thegrowersshop.co.uk/powerplant-aircooled-aerowing-reflector-with-5m-iec-cord-set-373-p.asp

for 70 quid they are top notch and also quite big and the full hood and glass get barely warm, my plants could touch the glass and would be fine,

That looks like a sweet bit of kit for 70 quid ! Much cheaper than the Magnum I was looking at. I reckon my budget could stretch to that in order to save my ladies anymore stress ! Really appreciate the advice

What extractor unit would you recommend for that hood ? I want to keep noise down if possible and how would I integrate it with my carbon filter ? Would I remove the extraction system I have right now and use this ? Does the hood have any external intake from air within the tent ? Or would I need 2 extractors working at the same time ?

The leaves that have already gone crispy.... Should I remove them at all or just leave them ? If I remove them shall I remove the whole leaf right from the stem ? Or just the crispy tips ?

ive got the rvk 6 inch fan (450 cfm) going to my hood then on the other side of the light ive got ducting going to my carbon filter above, so my fan is cooling the light and the room at the same time, the light itself has got 6 inch flanges so a 6 inch fan is the easyest option, but you could use reducers so your fan fits, whats the cfm of your fan? it looks like a 4 inch TT fan which i dont think will be enough to cool the light and room but i could be wrong, you could give it a try and see what your temps are like,