Fan on while lights off?

I am very new to this. I ahave a buddy who gave me some plants that are vegging. They are almost ready to start flowering, should I leave the fan on while the light is off? I don't really know, and he won't be back to check on me for a couple of days. It seems they are extremely moody girls ( a true women, huh!) I have had some issues and went to H20 only and they perked back up. He is also bringing me a PH meter so I know that is going to make a huge diiference. I think right know they are a little low on N, but it can't get it until the PH is right. I will take some pics in a couple of hours (Dark now). Thanks for any help!!

You should leave the fan on to prevent air stagnation....
I think they appreciate the breeze.
I keep my plants ventilated 24/7

Yeah u can leave the fan on, its good for making the plant grow stronger stems.

The fan doesn't have to be on all the time. Just like in nature (think summer) it isn't breezy all the time. Constant wind blowing on your plant isn't good either.

i got my fan on the same timer with my light

Leave the fan on. We are trying to duplicate Mother Nature. Just a gentle breeze will do.

Vi

Correct.Leave the fan and exaust on 24/7 this will help prevent mold and help with co2

at least leave it on with your lights, and leaving it on all the time will not hurt your plant but don't let the wind blow your plants over thats bad

I keep mine on high facing away from the plant, drawing hot air out of the grow room during the "day". At "night", I turn the fan to ossocilate on low speed directly over the plants...

during the day i face it away on high, night i leave it just above them on high but it's a little fan.

KEEP THE FAN ON HOMIE! at all times, i have a moving fan i keep on 24/7, like you have herd a few other times, it will prevent stangnit air, helps to scare off pests, helps with mold and fungis, and gets the H2O to your girls.
so do them little sluts a faver and keep em on,
\ happy growing
goodluck!
seattlewise ass

oscillating(sp?) fans are good to leave on 24/7 to circulate the air.. a fan blowing directly/party on a plant straight for long periods of time however will give the plant windburn