How much height do you have to work with? I wanted to keep mine at about 2-3 ft for my first time around so when they were around 12" tall we flipped them to 12/12. They usually grow about 2-3 times their height during flowering so keep that in mind. You will yield less if you flip them when they're smaller and immature.

HPS bulbs are fairly hot. I have 2x 250W lights on in my room right now and they are heating my entire 1 bdrm apartment, with the window in my room open most of the day for fresh air to get in. I'm in shorts at 9:30am and it's warm. There is 3" of snow on the ground outside. Point the fan at the hot air under the bulb and above the plants you should be able to put it about 3ft away for now. Possibly closer but I'm not sure if that'll be too much shock so it's best to start further and move closer than the other way 'round.

-canuck :jointsmile: