Hi there SeaLevelGrower,

1) If you can see the light of the grow tent, thru your garage window then light will surly be seen inside the tent when the light is off; either natural light thru the window or when you turn the lights on in the garage. Not a good situation beause 1-it's a hermie farm waiting to happen and 2-someone is going to tell at night you have and HPS light on all night.

2)Yes, especially if causes light leaks. I assume the Vortex is a 6" diameter, so with that a 4" passive opening is sufficent, tho if you don't believe in the physics of same volume out mean volume in moves faster thru a smaller opening, then use a 6" inlet. I would consider putting a 4" flange kit on it for intake, mount a flapper to it (like used for dryer outlets) so that it opens when the fan is on and closes when the fan is off. On the inside of the flange I would put at least one 90degree elbow, painted flat black inside, and put some sort of filter to the outside. This could be just a piece of nylon hosiery or a generic round car/truck air filter with a 4" opening.

A couple of things to consider doing also. You can run a 4" dryer hose from your inlet to the wall of your garage, drill a hole and mount a clothes dryer outlet and use it to get cooler air from outside, if it is cooler outside then in your garage. Also important is to get as much of that 1kw bulbs heat out. I would get an air cooled hood and attach a 6"diameter hose from one side of the hood to your Vortex fan / charcoal filter and leave the other side of the hood open. That way you can get air in, plus better cool the light all with one fan. Keep in mind that this needs to run whenever the light is on, ie; same timer.

Hope this helps, good luck growing. :thumbsup:

I just though of something else to add, but I just had a med induced brian fart, and can't remember what it was. If I can pull it from my poor old brain, I'll add it in another post.