I am running 2 x Spider Farmer SF4000s LOL, overkill yes, but i only run at 80% and i get max coverage. all up its 900watts from the wall @ 100%, so around 700ish @ 80% ? i usualy have them about 20 inches from canopy... This achieves a PPFD off about 650 to 700. Thats somthing im learning about...