New GrowTent Setup advice needed please.

Ok so i recently finished my last grow inside a 3x3x7 ft growtent, using 2X600W HID lights with a 6'' intake and exhaust fan.
This grow ive got a tent with a touch more space its a 4x4x7 ft tent, and heres the kicker...
I've purchased and added a THIRD 600W HID light.
Ok so where im confused is with 1800 Watts of HPS/MH light inside such a small space im going to be raped with heat issues.
I've purchased a secondary exhaust fan or booster fan if you will, so i can run that half way through my duct line as its going to be extended i dont want issues with not venting enough heat/hot air out.
Should i do ok aslong as ive got oscillating fans to cover whatever heat spots may arise?
Im aware of the elec cost for this tent, and its not a big deal as im trying to get as much as i can from my space.

You are a bit nuts.

You need to realize that there is always a bottle neck issue than limits growth. Even at half the amount of light you are talking about, light is not the bottleneck issue. At the levels you are talking about, I doubt light would ever be the bottleneck issue.

To use anywhere near that amount of light you would need a sealed room, elivated CO2 levels, much higher humidity, and you must run Hydro at high PPM (nute uptake from soil will not be fast enough, it would be your bottleneck). If you don't do all of these things, it is certain that one of them will be your bottleneck.

Don't go Ape-shit over one aspect of the grow. You need to upgrade all aspects at the same time or just upgrade the bottleneck to see any improvement. I wouldn't put the 3rd one in there. If you are nuts enough to do it anyway, at least put a MH in one of the three so you have some blues for better potency than HPS alone.

You might want to upgrade to 8" or 2x 6" exhausting if you are going to attempt this much light in that small a space.

i have 2 6'' exhausting.
I am Using coco-perlite medium.
I am also using 1 MH in the centre of the room, and 2 HPS on the outside of the room.

over kill on the lights for a 4x4 area you only need 2 600w and put the other in the 3x3

yeah 1000W is all you need for a 4x4, try adding led for spectrum or topping methods to achieve 1gpw/ set up a veg tent and 2 flowers, you have enough light for 3 tents now.

Man im running 1 600w in a xxl hood in a 4x4x7 and it is kicking so far. 2 600s is like wow 3 is a waste.