12-20-2004, 03:48 PM
Join Date: Feb 2003
I assume you are planning on using HID pendants. You have to know the dispersion angle for your pendants, then do some ray tracing through the water to get the optimum height. Don't forget to add in the refraction at the water's surface. Otherwise (if you hate to plan stuff) move them up and down over the tank to find the optimum height by trial and error.