1. You should never add uncured live rock to the aquarium. Doing so can release harmful levels of ammonia into your aquarium.
2. Goldfish can live incredibly long periods of up to 25 years. You should plan accordingly when you purchase a goldfish.
3. You should always research the different types of fish you are going to be housing together. Certain fish can be extremely aggressive and cannot be paired with other fish of different temperaments.