I'm planning to do a 12/12 from seed grow in a PC grow box, but I don't know how long the fans should be on. Should they be on as long as the lights are on or should they be on 24/7?
you should have an air exchange at all times. if you run a fan to blow on your lights, you can have that turn off when your lights are off, but all other fans for all intents and purposes should be left on.
that is always a worry, but one we must all contend with. if it is a big worry on your mind, then add a sencond fan every where you plan to put a fan. that gives you some redundancy. hope this helps
