Yikes! 30-40 Celcius is 86-104 Fahrenheit!

Even that is still a tad to hot...I'd say you'd want to really stay in the 75-85 range....rarely going over 90...
BobBong Reviewed by BobBong on . temperature question hi all, first post. strain - dutch passion (fem), oasis (northen lights #2) space - wadrobe, just under 4 sq foot, height 6 ft lighting: 40w cfl (seedling's), 250W blue envirolight (veg), 250/400w red envirolight (flour) venting - passive (semi open door) / 6" desk fan. Rating: 5