Need tent ventilation advise...

I've been growing with 1k watt hps for years, using an 8in hyper fan to push air thru 3 hoods into a separate room. Thus utilizing the heat during the winter, the only time I grow.




My room is in the basement, walled away from the living area and only accessible via an exterior door. It's cold! Probably mid-high 50's when there's no grow. I've been using an inkbird controller with an oil heater to keep it warmer during lights out, it's still cool, hard to hit 78 when lights on. 1k's




Well last grow one of my ballast lost a transformer and I ordered up an hlg 600r-spec to sit in it's place. I like the light and decided to switch out my remaining 2 hps in favor of leds. I went with 2 320w build kits.







So to my question... I figure it'll be easier to get tents to make temp control manageable. I was planning on getting 1 4x4 for the 600 watt light and 2x4 tents for ea of the 320w lights. I'm planning on leaving the hyperfan/filter in place running at a low speed, and keeping the inkbird controlled oil heater to keep the room warm as before.






What kiND of ventilation will I need for the tents? Will 4in fans cut it or will they need more? At first I figured I could use 4in booster fans but the more I read I'm doubting that would work.





Those of you that use tents, what are your thoughts on my cold basement grow space?

In my 2x4x4 tent I went with a 6inch inline setup because that's the largest my tent would take as far as inlets and outlets. One on top and one on the bottom of the tent on the side walls. I always go with the biggest fan so I can run the fan at slower speeds which has helped out with air movement noise.

My initial thought is you will end up using more heaters to keep your space warm. You've cut your wattage in half.

But yeah by the sound of it 4" fans would probably work with your particular cold environment.

Don't bother with booster fans though, they don't do shit. I bought one once for my drying cabinet and it couldn't even move air down a meter of straight duct. Smoke tested it, no air movement.

I'd be tempted to run a veg tent with bulb and a 4x8 with all your leds and feed the warm air from veg tent into the flower tent, that's if you have the room.

Your veg plants won't mind the cold as much due to radiant heat and your flower plants won't need as much heating.

I run similar sized tents in a similar environment, 50's ambient temps and 60+% humidity. I have to run HID lamps most of the year to maintain temps inside the tents. I have to run heaters durring dark periods to avoid massive temp drops and humidity spikes. So that's my experience, it's definitely do-able, maybe just not as economical as it could be.

As far as ventilation, I have to run minimal cfm (Just enough for minor negative pressure) otherwise all the heat gets sucked out. But you gotta keep up enough exhaust to manage your humidity. Its the environmental dance that you'll probably play for a few grows until you figure it out.

But the bottom line is, as long as you are willing to condition your lung room with a heater, youll be fine and you wont need much cfm at all for cooling purposes. Good luck!