the t-5 in in the center, t-8 to the right. The t-5 is the way to go. You can honestly let the plants touch the bulb and they dont burn. I had a mother grow between 2 bulbs, funny shit.

Lighting is another opinion filled deal. here is mine.

The closer and more intense the light the faster the growth. I had people tell me you cant bring a light to 24" of a plant or it will heat stress and die. At this very moment I have 1000w hps bulb about 14" from the colas.
You see its all in the setup and what it can do. With chilled water the plants can take more heat as well. You will also see people blowing the plants sideways with 10 fans. Crazyness. I have 1 fan pointed at...yup the sky on the lowest setting.
not my plants, not the bulbs, the sky. Why? Cuz IMO you need the air on move and mix thats it. We never blow plants sideways in a greenhouse of tomatoes and face the exact same problems prob even more.
People often miss the point that heat rises and you should be skimming this hot layer off the top not spreading it all over.