How long do i leave the fan on for indoor grow.

how many hours do i leave the fan on for growing weed ?

24/7 why ? because when the plants are small they need that extra wind to make the stocks strong as if they were going to be grown out in the wild. Plus it helps circulate air in the closet a must because you need to move air around.

agreed. unless its a light cooling fan then only the hours the lights are on

all day ok got it. but if my plants have stong stems can i shortin it