That's a good thought, rosy, about the onions, but spores like that ride the air currents for miles, so one must assume that the potential for infection is always present, especially if you live in warm climates and don't have cold winter.
I have Bee Balm in the garden that gets PM at the end of the season, telling me she is done for another year. Lilacs and roses get it too.
Obviously any filtration is better than none. A 3M high end furnace filter sealed on the intake will help with mold, fungi, insects, pet hair and other contaminants. I would highly recommend this upgrade to everyone, it will cut down on airborne problems. Plus no one wants pet hair in their finished bud.
Obviously once you open the door it bypasses all filtering capabilities, but it is still much better than a straight open intake, sucking potential problems into your grow space, 24/7.
"That's good Pete, pot..."
"By the cold and religious, we were taken in hand..........shown how to feel good..............and told to feel bad." - roger waters
Last edited by HeadyPete; 01-29-2008 at 05:49 PM..