1. It is good to budget out the cost of your aquarium. You should leave plenty of money to purchase quality filters, pumps, and heaters for your aquarium. Your big aquarium is going to do you no good if you do not have the proper equipment to keep it going.
2. It is not a good idea to wash your filter media with regular tap water. The tap water can kill the beneficial bacteria that is built up in the filter. Use distilled water to clean out your filter and its components.
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.