Well lets hold everything up here.
You can't add any fish or inverts until you complete a nitrogen cycle.
Some people say you can do a fish in cycle, but that's fish murder. Sorry.
Nitrogen cycles can be completed with plants. You dose either ammonia or fish flakes daily, and see if your ammonia drops by the end of the day. It is simple. It takes time, but if you don't take your time and do things right, you'll regret it later on.