1. If you use your tap water, you should make sure to remove the chlorine from the water before you add it to the aquarium. Chlorine can be very harmful to some of the fish in your aquarium. You can purchase kits to remove the chlorine from your aquarium at many retailers online.
2. It is a good idea to clean your aquarium with a soft wash cloth and warm water. The soft cloth will not leave scratches on the inside of your aquarium and will remove any unsightly stains.
3. Pay close attention to your fish's PH needs and augment your aquarium as necessary to accommodate the new fish you are adding to your aquarium.