How much watt of red+far red light in grow tent?

I have a 4x4 tent with 3 240w quantum board (720w total). Im interested in adding red (660nm) and far red (730nm) lights. How much should watt of red light should I add? I already have 2 7w far red pucks from rapid LED.

I use (2) g8 led booster ufo's. 90w each, only 660nm

4x8 is my area so for a 4x4 you could use 1

I wish. A little bit expensive for me. It's 180 dollar and that is not including the shipping and tax I will have to pay to bring it to my country. I'm thinking of building my own. Looking for a diy build