Hello Heip and welcome to TRT. First of all Bio cube are wonderful little tanks. I have an 8 and love it. There are a few things you might want to do first before you start your tank. Now remember these are just my opinions you should do a little research on them before you make a decision, and I am sure others will chime in as well.
1) Take all the bio balls out as these are nitrate factories. In the middle chamber or chamber 2 I installed a bag a carbon, rowaphos, and ceramic rings. Chamber 1 50 watt stealth heater. Now one thing that I did not do is install a
http://www.nanotuners.com/product_in...roducts_id=309 This will help keep the temp down.
2)Salt is a good question I use
Tropic Marin Pro Reef. But a lot of people on here use Instant Ocean. There was a pole done not to long ago on this site on salts so type it in the search.
3)As for live rock I think 10-15lbs would be fine. Make sure it is not too dense of rock.
4)sand is cheep it will eventually turn into live sand so do not spend a lot on the sand.
5)For a clean up crew a couple
nassarius snails, 1 conch, 3-4 hermits, and a couple a margarita snails.
6)Salifert is the only test kit that I would use. You will need calcium, nitrate, nitrite, ph, ammonia, dkh/alk, and that should get you started.
Put your sand and cured live rock in the tank and let it run for a month or two before you and fish or corals.
