Hello, I am planning to start my first Reef tank and will surely try my hand with the ATS from the start. I will feed my ATS with the separate jebao DC pump of capacity between 235-530 gph which will give me flexibility to increase or decrease the flow as per the performance later. The light i will be using is 660 nm and 450 nm blue on both side of the screen. The thing which is bothering me is the placement of the Ats and the screen size. I am not too sure whether to place the ATS pre skimmer or post skimmer also the size of screen which i have to use to handle the load which i will be facing once the tank is fully stocked also the height of screen above the water level. Experts out there please help me.