1. When you purchase your aquarium and the equipment for your setup, do not purchase the fish at the same time. You are going to need plenty of time to cycle the water in the aquarium to make it hospitable for the fish in your aquarium.
2. After establishing your aquarium, pick fish that will add well to the current water conditions in your aquarium. Also be sure to check their temperament and other needs to be sure that they will make the transition in your aquarium smoothly.
3. Some people go by the ìinch of fish, gallon of water rule when deciding on how large of an aquarium to buy. This is a completely false and bad method to go by, you should always check your individual fish's tank requirements.