Light distance

My 2 cents, as long as you are hittingthe ppfd and DLI goals and not getting so close as to cause heat damage to the plants you are good to go. Also the closer the light is the more concentrated the area of high par/ppfd, so the edges of the tent may not get as much light, but if your plants are not too big and filling tent up yet I'd go for it. I also have a tsl2000, I love that light, perfect for a 2x4 tent, but have it as a back up for now, not enough room to be running all my gear. Good luck and happy growing.