1. Goldfish can live incredibly long periods of up to 25 years. You should plan accordingly when you purchase a goldfish.
2. Do not overfeed the fish in your aquarium. Keep your feeding times at scheduled intervals to avoid overfeeding. If you are just starting your feeding routine, start out small and increase the amounts you put in on how much your fish eat.
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.