Congrats! Sounds like a very nice system! I'd start it in around 8.5" of water. Pump speed between 28-32 watts and use the wedge pipe to get the line where bubbles turn to foam at about the white collar where the cup attaches to the body. Since you have a low load right now, you could go as deep as 9" in which case, you won't need to close the wedge pipe as much. Once the skimmer breaks in, find the sweet spot on the pump speed that makes for the most dense foam. Keep in mind that skimmers need dissolved organics to create good foam and because your load is going to be low for a while, any adjustments you make once it breaks in will likely change a bit as the load increases.