I personally would keep the light fixture vented.
The way I see it.
Your light bulb (I forget what it is) I'm assuming is rated to be in an enclosed fixture.
This is to contain the bulb if it failed and blew (cracked, burst, came apart) it could send molten hot chunks of glass and metal raining down on your plants, tent, pots etc and possibly start a fire.
Having an an closure to help contain the burst parts coupled with having a dedicated airstream to rapidly cool the heat contained within them. Helps drastically reduce your chances of starring a house fire.
Being in your basement it would ignite your home from the bottom up.
Just be safe!
The other reason I'd keep it air cooled is that you can drop the light down within inches of the canopy (I've done "3-"4 with my cooltube).
You would be able to focus the light on the smaller plants this way at the beginning. Then as your plants grow tall you raise the lights to accommodate height. This increases the footprint also accommodating them as they grow wider.
Doing this keeps a consistently dense light source on your canopy at all times if the distance is kept consistant and adjusted every so many days.
The goal is to keep the light as close as possible to the canopy during all phases without inducing heat damage, or light burn. This helps provide the canopy (which takes in the majority of the plants light) with peak environmental light potential. While also providing the lowest flowers with as much light that remains once the canopy is done with it.
Well use the inverse square law of light to explain why keeping the light as close as possible is ideal.
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The pictures use meter as distance for visual aid. But the equation can be scaled to any distance (mm, cm, in, ft, meter) so the key concept here is "distance" from the source. Just replace the meter with distance.
Now if your glass is off and the plants react poorly you will have to raise the light up higher. Drastically reducing the light the lowest point on the plant gets.
Whereas keeping the light air cooled & closer to the canopy gives the lowest part of the plant much more light helping average out the quality of your finished flowers top to bottom.