You should start the cycle with something like a raw shrimp or some fish food. I don't think your cycle has even started because your ammonias should be up today. Once your ammonia goes up, then the nitrites, then the nitrates. When the nitrates are almost down to nothing, like 20 or less, then add a few hermit crabs, some snails. After they have been in there for a week, check your levals and if everything is good, add your first fish. You won't want to add another fish for another couple of weeks.
Unfortunatly you can't have a yellow tang in a 29 gallon tank, they need at least a 75 gallon, some would say a 55 is ok, but not a 29. The clownfish is fine for your tank. Go by the an inch of fish per five gallons rule. Some will not agree with me, but I think this is a good way of starting out your tank. Now those inches are for a full grown fish. Some fish don't swim much or are very big, so they can be less than that. Some fish swim a lot and need a lot of algae, so they would need a bigger tank, like a tang.
Some fish you could have in there with the clown are, a firefish or another type of goby, a cardinal, a six line wrasse, royal gramma. You could try a pygmy angel, just make sure your tank has been up and running for a couple of months before it goes in there. I hope this helps you, patience is important in this hobby, don't take things too quickly.
