Glad to help if I can and happy to hear that my trials have been an inspiration to some people. Apologies if I came off condescending at all, as it was not my intention. It's just that there are soooo many noobs coming through that think they can throw some seeds in dirt and grow dank. But I think you're definitely on the right track and doing the right things :thumbsup:

I'm still a little unclear about your enclosure, if it's light proof you should be able to make an exhaust hole and intake hole. Unless of course there are walls and doors that you don't want damaged. Regardless, that HPS will bring the temps up over optimum without good ventilation.

My very first grow I only had a 400w hps and a large fan blowing on my plant. I had a cab that I could close for the night, but no way to keep the door closed or even slightly ajar without huge heat spikes. By the end of flowering, my whole apartment building stunk like a skunk.

Even without venting, you can still use a carbon filter/fan combo to clean the air, it just won't work as efficiently. Growers using CO2 do this in closed rooms since they don't want to vent out the CO2. As long as the temps are in range and the plant gets plenty of fresh air, the ventilation is not really a problem. The problem comes with the paranoia of thinking everyone who passes your house knows what's going on in there. Even worse is that you get used to the smell, so you won't really know how much it stinks until someone else tells you.

I don't see preflowers which are very small, fine, white hairs. Check here: Text This whole guide is really a good place for almost anything you want to know. I just click CTRL + F and type in something like "preflowers" and it takes me to it. CDOT guide

Hope things go well for you and just keep reading and asking questions along the way.