Pics: Leaf Problem!

These are 7 NL clones that got off to a very bad start after an invasion of mites attacked them as babies. Mites seem to be gone and they're approaching healthy again after a nasty chemical battle, though still a little bare from removed necrotic, egg-infested leaves.
The little runt in the middle, back row, was a goner, but she's come back for another go at life.

Anyway, the pale blotches on the leaves? a couple of the gals are showing the same symptoms. Slightly curled looks like heat issues which I cant do anything about because I dont have the capacity to get around the hot summer temps, so I'm expecting that, but the pale blotches look like a PH prob?

Heat is the problem, sorry to break it to ya, you HAVE to deal with it, or consider moving your grow outdoors.
High temps exacerbate other problems, and yes, the pale patches are likely a secondary effect of the heat.
Chlorophyll starts to break down in the mid 90s. Enzymatic processes grind to a halt. No amount of food, water, or foliars will solve the problem if the plant lacks the enzymes to assimilate nutrients.

Hmmm, interesting. I'm seeing this as an experimental grow. Only two plants show these signs so far though, probably due to hotspots in the room.

What lights are you using, how much watts????????? Maybe you should use only cool lamps at that point, or a less watt lamp

400w HPS, big ass vent, but theres nothing I can do about the hot summer air going in, giving where the room is situated. Growing outdoors is also out of the Q. So, just an experimental grow, I'll know first hand in a few months what happens when the temps are high.

Meanwhile the next autumn batch will be kick ass ;)

That brings up a good point... you might consider scheduling your grows so that during the hot period of June-August, you concentrate on propagating clones, doing maintenance on the room, and starting seeds, and leave the HIDs turned off entirely. A grow buddy of mine is doing that actually! It's not a bad way to save the frustration of dealing with heat problems, and then when September brings the cooler days, you will be ready to go.
My last piece of advice is to cool your house as much as possible the way I do it:
Every evening at about 6 when the outdoor temps drop below what your house has heated up to over the course of the day, OPEN all the windows and get fans going... leave them open all night (run your lights only at night too) and then at dawn, shut them and draw the curtains. You will be amazed how much $$$ this saves on a/c too. HEAVY curtains that can darken a room should be used on any windows with S/W exposure!
Good luck...

Actually, half of the point of this growth is securing good clones for the autumn. Apart from that, I already follow most of your tips, windows wide open at all times, I open the front door for a few minutes several times a day to exhaust the house with a draught, etc.
But we're hitting over 30c outdoors now, so any serious attempts at growing right now are thwarted (can't fit an AC in the room)

Thanks for the tips :)

Any idea of how these will turn out?

Bah, gave up and switched to my 250w HPS and moved it as close as I could (about 30cm) and got the temps down to 30C.

At least I'll get a little bud from those 7 gals lol.

stinky is correct in saying to cool the room at night(windows open), then let it the room heat itself up during the day (windows closed) if you leave the windows open it'll get nearly as hot as outside air (rather quickly btw), it won't if the windows are closed when its hot out. I cool my garage at night (with fans) then shut the windows during the day (so the growroom sucks only from the cool garage that is already cool from the night before and the cement floor) some days it makes a 20 degree difference between outside and inside. no reason to take down the 400 watter! just be diligent!