How to let air in and keep light out

[crunchyfrog]

My first grow, flipping to 12/12 today. Four WW plants in 4x4 tent. I have an exhaust fan with carbon filter and up to this point I have left the two small rectangular vents at the bottom of the tent partially open (opening towards the floor only) as well as the bottom of the front door unzipped to allow fresh air to be pulled into the tent. The tent is in a basement that has two small, frosted non clear windows that have dark fabric on them them to help keep the light out however, since there is currently more than 12 hours of sunlight during the daytime, there is a small amount of light before sunset and after sunrise that is in the basement area.

My question is should I worry about the openings in the tent that are currently letting air in now that I am in the flowering stage and if so, how have you set up your tent to let air in and keep light out. I guess I could try to completely blacken the two small basement windows with cardboard... Other suggestions/comments? Thanks!

[F10werChyld]

Black out the windows, that will help. What I do on my tent is drape black cotton fabric (like an old t-shirt) over the vents. However, my windows are completely covered.

[Eliot Pryor]

I been growing in my garage. Light leaks have always been present. Flowered dozens over 6 years. Forget about it.

[dphipps1020]

The tents are designed to let air flow in regardless of the flaps being open or closed. You want negative pressure, meaning the walls of your tent will bow in when the flaps are closed. If you leave the flaps open during flower, when the lights are off, you're just asking for your plant to herm. It may look like your tent is going to implode, but it will be fine.

[crunchyfrog]

Thanks for the responses, I am going to put cardboard over the windows for now, easy to do, no cost, cheap insurance. With the cardboard, there will be zero outside light in the grow area/basement. I do wonder though if Eliot Pryor is not correct in that I could just keep going with what I have now. I mean the bottom vent flaps are opened to the floor so only reflected light could get in from the floor and would have to be reflected again to get to the plant. I cannot see my hand now at sunrise and sunset in the grow area with just the dark fabric covering the windows so the amount of light that could get inside the tent (at the edges of the lights on period) would be very small. Maybe some others can chime in how they have fared with very small light leakage at the edges of the lights on period.

[Tersky]

My 2 cents is i have had pinhole leaks and zipper leaks re-veg a plant so take that for what it's worth. That being said, i have a sliding glass door in the room across from my tent and it happens usually in the summer when i have to keep my lights off during the day for heat reasons. As long as the room is dark you should be fine but i prefer an abundance of caution. One thing i have done is velcro on some carbon filters over the vent holes. This helps filter dust and hair (have a dog) and blocks light. This is what i used and just measured and cut. https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1
I had to get some velcro strips separately.

[Sudsnbuds]

I built his grow box in my garage, to have something more solid than a tent. Problem is the same as yours, getting fresh air in when it needs to be dark. I cut a hole on top and used old tent vent hole fabric to put through it. Then stuffed a bunch of air filter refills in the hole. On the back I stapled a bunch of furnace filters over a hole. I can still see small amount of light coming in. I have a dehumidifier in the box. 12/12 for almost 4 weeks. The light leaks aren’t a problem as long as you keep the cycle on a consistent timer. I open the door a bit when the light is on, just to get as much fresh air in as possible. Works well. Only issue is when the door is closed the humidity goes from 40% to 55%.

[Tersky]

A little defoliation can bring down humidity and is another reason i do defoliate. Dont go crazy since she's in flower but it will also help with airflow. 55 isnt horrible as long as you have good airflow.

[Korn]

I have a set up like yours. No problems. Not enough light will reflect up through your lower vents to cause problems. If you want to block the windows with cardboard to be sure that’s cool but if you don’t I believe you will still be fine.

[Toker1]

Agreed with above. Not enough light to set off an issue. If you are really concerned, place an object that casts a shadow over the open flaps, but distance it far enough to allow air to easily pass through.