A lot to take in!!. Please note that when adding fish food to tank, to create ammonia, to feed the bacteria, it can take up to 6 days for the food to rot into ammonia. So when adding some food, wait and see how long it takes for you to see ammonia, then see how long it takes for the ammonia to go down, before adding more food. If the ammonia goes down in 12 hours or less, then your tank is ready to go. If it takes longer for the ammonia to go down then you need to add some more food. Keep adding some food, and testing to see the ammonia spike and, how long it takes to go down. It can also take Up to 6 days for dead stuff on live rock to rot into ammonia, so wait at least 6 days before adding fish, when using live rock. Dead/dry ocean can have dead stuff on it. It can be live rock that has been dried out, so all the sponges and coralline algae is dead, but still on the rock. This will mean a lot of dead stuff for the bacteria to eat, but also a lot of phosphate and nitrate, being produced by the dead matter on the rock. Placing the rock in some R.O.D.I water, in the tank or in a plastic trash can, for a few weeks, will help remove the dead stuff. A 100% weekly water change can then be done to help remove any phosphates and nitrates. If you are adding the rock to an established tank or an upgrade, you need to make sure the rock is completely free of dead matter, and ammonia is zero, before adding it to your tank. If it is a new tank then a bit do dead stuff is O.K. The dead stuff will rot into ammonia, and feed the bacteria to help cycle the tank. Only when ammonia is zero ,do you add fish to a tank. If your dry ocean rock has no dead stuff on it, it is still a good idea to soak it in some R.O.D.I water for a few weeks, to remove any phosphates. Every thing you need to know about mixing up sea water, dry rock, dry sand, live sand, the nitrogen cycle, and adding fish. You could mix the salt water in a separate container. Easy if you have a 10-20g tank. Not so easy if you have a 55g+ tank. That why I say to mix the salt water in the tank. You could use a large trash can or similar. You tank has a heater power heads and skimmer to help mix the salt. You could add the sand first, (live or dry) then push some of it to the side, so you can put the rocks on the glass bottom of the tank, before moving the sand back around the rocks. You could build the aquascape in the tank with out water in it. Just remember the live rock or live sand should not be exposed to the air for more than half 1 hour, so it does not dry out. You don't get this problem with dry rock/sand. The salifert test kit shown, dose not test for both forms of ammonia. It is an O.K test kit but not the best. When aquascaping your rock, try to make it as open as possible, with caves tunnels and islands. If the rock is pushed back against the back wall, (in one pile) any rock face that is not open to the water flow will not be live. The bacteria on the rock need a constant flow of water be survive. Open rock work will also help prevent build ups of fish waste. The rock can be glued together with reef safe coral glue, or reef safe epoxy putty.