Awesome collection you got there. The tank looks really clean too.
I think I might be inclined to have a thin layer of black sand on the bottom, a black background and white marine lighting. That would bring out the colours in your fish like you wouldn't believe.
sounds good bro...I had black sand before..they are nice..it's just.. I like no sand or gravel because I dont want any sand going to my filters and also like my filter to do the work instead of me vacuuming the gravel...but I do agree the sand will look really nice...thanks bro.