For the cube I would do one title packed array. If you have two arrays (ie. two light sources) you'll probably end up with colour separation and get that multicolor shadow disco effect. If it was a long tank, you'd need two clusters for the coverage but with a cube, you'll probably get enough spread from a single array. On my biocube is use 22 LEDs (granted many of them are 3-up stars) packed into a tight rectangular array similar in shape to a metal halide reflector. Works well.
I would also recommend adding some ocean coral white and true violet LEDs to that mix there. For me they took me LEDs from meh to awesome.
|