1. When starting out a new aquarium, it is best to add hardier species at first. Once your aquarium ages a bit and gets settled, you can start to add more sensitive fish to the aquarium.
2. You should be sure to rinse out all of the materials you are going to be placing in the aquarium with water. Do not use soap or detergents, soap can cause toxic results for the fish in your aquarium. Just rinse the equipment with distilled water.
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.