Very nice-looking tank, thank you for sharing with us
My guess is that you are using a combination of mainly metal halide with a few actinics and 50/50 florescents.
I wish my shots would come out that nice. I think my camera only has 3.5 megapixels. It looks nice on my end, but for some reason when I upload them to this site, they get butchered and all fuzzy and unclear.