Due too inadequate exhaust fan I had fought high temps with all previous grows. Finally put a crowbar in my wallet and got a decent fan with speed control. Now temps are in low 70's during the day and upper 60's when lights are out. Is this too cool? Because of small grow area I had to put previous grows in flower around week 5 or 6 but this grow looks like it could veg longer. I kinda like that idea as the breeder says potency and smell could improve with additional veg period and I have stash left over from previous grows. Are there any concerns I should have vegging in these temps and is it cool enough to retard growth?