New biocube 14 questions

I just got my new biocube 14 and I'm starting to plan everything out. 1st question I am planning to use live black sand so I was wondering if there are any flaws? 2.) how many pounds of live rock should I use? 3.) How many hermits, snails, and what shrimp should I get. 4.) Could I keep two pearly jawfish in the tank? 5.) Any other recommendations I should do? Thanks!!