If you plan on absolutely filling up that tent you want a minimum of 30 actual watts of light per sq foot. 35 to 40 is better, per square.
An LEC 315 watt Ceramic Metal Halide can cover 3 x 3 feet well.
450 to 500 watts of Cob Cree led or the same amount of HLG Quantum Board led would cover all 4 x 4.
Some folks use dehydrators late in flower to lower humidity, eliminating the chances of excessive humidity or bud rot. Most use a fan or two. So many dont use up all their available space in their tents.
Assess how you wanna roll, how much footage u need for LIGHT , plan on 35 watts per sq, as a minimum. 40-45 watts per square is better.
Purple or Pink lighting will work, but light fluffy popcorn buds, usually. (Fuck BLURPLE lights)
WHITE led lighting or CMH lighting is a closer spectrum to the sun. You can actually see your plants well to observe problems that may be happenin. And the growth EXPLODES.