1. Goldfish can live incredibly long periods of up to 25 years. You should plan accordingly when you purchase a goldfish.
2. Only use medication in your aquarium when you are out of other options. You should use a separate tank to medicate sick fish as some medications can have harmful effects on healthy fish.
3. Stingrays make wonderful pets for the aquarium, but make sure you can properly care for your stingray in your home aquarium.