Cycling question!

You need to be adding a source of ammonia to get the cycle started and to keep it going. That source could be ammonia from the store, fish, or fish food. Otherwise your probably looking at a very long cycle with a small bio load.

Most of the folks here will opt for the fish less cycle method in order to avoid distressing the fish at all. If you have an existing tank or a friend with one you can use it to seed some filter media with bacteria and that will speed the process up considerably. I normally opt for that together with adding a 1 or 2 inexpensive fish, then after a couple of weeks add a couple more fish, and so on until the bacteria have had a chance to grow and become effective. Keep sniffing your tank and if it begins to have much of an ammonia smell do an immediate water change of up to 50%. Do regular WC's anyway at least once a week and don't disturb or clean your filter during this time. It takes longer than a fish less cycle but if done carefully it won't stress your fish.