is 70 degrees to cold?

i just got my fans running in my grow box i now have airflow but now my temps max out at 70.. is that to cold? should i turn off my intake fan and just have the exhaust running?

70 is fine, when lights are off what is it at? Your drop might end up a bit too much.

mine stay at 70/78 and thats perfect for my girls.. but i also put a space heater in there at night when its really cold

70's perfect..... something like 50 or so would be too cold

lights off it drops to about 66.. im in my second week of flowering.. will a little bit warmer temp do them better?

70's...rally? I have been told by some of the best (old timers) growers that 80 is what we want and a 10 to 15 degree drop when lights are out will make the buds harden up.
When I first started asking questions I was told that 70 is the perfect temp. So I kept my girls at a sloid 70. Growth was very slow. When I bumped room temps to 80 my girls really started to show growth. I could see height difference from lights on to lights off. An inch in height and girth as well is not uncommon.
Call some grow shops in your area and ask detailed questions.
Keep in mind that I am talking soil so your milage may vary.