Professional Advice - Trying to beat the Cold

Hello, and thanks for clicking. I love this place.
I'm hoping to do my first grow. I'm excited.
Here are facts:
Stealth
Personal style (1-2 plants tops at a time)
Small Box - As you know
Winter is Approaching
400 W HPS

My plan is to use a 80-95 CFM blower to pull air from the attic into box as ventilation source, then push that through carb filter as exhaust (Hoping for zero smell outside). Very Simple.
The attic can reach temps as low as lower 30 Degrees F.(Sorry don't know Celcius off top my head) So obviously this interior might get a bit frosty in mid Jan.

My plan was to run 400W HPS at night hours (when temps would be the coldest). Would this generate enough heat to keep my babies healthy?

I do not want to mess with electric heaters or such, as I honestly do not feel comfortable leaving that un-attended for hrs. at a time (I'm sure you would agree). If you have any experience using SAFE method(s) to heat a small area, I would love the wisdom.

I'm also prepared to wait it out and do this when conditions are better, so if it's a lost cause, tell me.
Peace.

a small portable heater would be fine because they only reach a certain temp and then they turn off themselves until the temp drops then they come back on and repeat the process. their about 30$ from walmart or wherever

no kidding. It still makes me nervous though, just leaving it. But, I've also never used one of these as well. 30 bucks is freaking sweet too. So how do you feel about that being in the box? Think my situation is cool? no pun intended.

ratatatisagoodband said:

no kidding. It still makes me nervous though, just leaving it. But, I've also never used one of these as well. 30 bucks is freaking sweet too. So how do you feel about that being in the box? Think my situation is cool? no pun intended.

Click to expand...

it's really no diff than running your lights or fans btw it won't take long for a heater to heat a small area so That would make turn on/off times with the heater minimal