Well it seems if you have that much space, well then you oughta build something that will take up that much space.

Actually sounds like a perfect space to grow one plant.

With the 4 ft. height though, be prepared to tie her down and bend her over and over.

Also, you might wanna grow 3 to increase the odds of you getting a female.

You got the grow container which will be how tall?
You have the light hanging which will take up how much height?

HOw much room does that leave you for veg and flower?

Maybe 2.5 feet?

Thats not a lot, but a low grow spread out and bent might be the best bet. When flower time comes around they WILL double in height.

Make sure you have indica dominant strain!!!

Finally, your 250W HPS will be enuff for this grow space. But plan on good ventilation with such a low height.

Yes, you can do it.