the great debate of black or white sand, it's a debate as old as time itself. Here's a few of my observations:
- white sand is much easier to siphon waste off of, because you can see it much better, which can also be a negative
- black sand can be more pleasing to the eye because you can't see waste, but that can also be a negative
- darker colored fish (Demasoni) will look nicer against lighter sand
- lighter colored (Labs) fish will look nicer against darker sand
I have white sand in my tank and it def makes my Dems colors pop, it's not horrible for the Labs, but I love how much easier it is to clean waste off of it.
If you're having a lot of trouble deciding, why not just get the black/white combo Cichlid Complete Sand that will also buffer the water, you might like that:
http://www.marinedepot.com/Caribsea...avel_Substrate-CaribSea-CS0772-FWPCPG-vi.html
Here's a vid of the sand in a tank:
http://www.youtube.com/watch?v=xz0FSZd2aaQ
hope that helped a tiny bit
P.S. the lights you use in your tank are also very important if you're looking for nice coloring, try 50/50's for a nice "pop".