Lighting in flowering room

Hello everyone,
Doing my 2nd indoor grow. Getting a little more serious about it now. My flowering room is 7x7x7 currently running 2x1000w hps in cool tubes. I have an extra cool tube and 1000w ballast.

Im considering adding it into the room in between the 2 hps lamps. Any reason this wouldn't be good? Ive got good ventilation so heat build up shouldnt be an issue in winter.

If you can handle the heat do it

if you want the most out of your lights surround them with plants
if you want the most out of your plants surround them with lights

consider a metal halide for your third, you wont regret it

Thanks for the response.