How long should I turn on ventilator?

[420BPM]

Hello everybody. I have recently bought a vantilator. I am doing my grow room on budget and bought a daily use vantilator. My intend was to keep it open as long as light is on yet my room makes lots of noise because of foil. I want to keep it turned off it as much as I can because its very disturbing. What's your advice? I have a 400w mh in room and room is pretty small (only one plant barely fit into) i havent bought temperature to measure it but my guess inside is somewhere around 30celsius
Thanks!

 

[Carcass]

30c is a little on the warm side,but it'll work-you don't want it much warmer,though.
Can you staple,tape,or nail the foil down so it doesn't rattle in the wind?
Are you using the fan to pull the heat out,or for circulation in the room?

 

[Captain Cannabis]

Definitely buy something to monitor your temps soon. If your space can barely hold 1 plant, that 400w light is gonna cause some problems quickly. As Carcass mentioned above, what you do with the ventilation is very important. My advice: draw the air out of the space, with the suction ABOVE the light. Budget a small oscillating fan, for the plant itself. Also, for under $30 you can get 10ftX25ft of white panda film for the walls. It will reflect light better, it's easy to wash/keep clean, and best of all--it's way quieter than foil. Goodluck!