1. A Fish Tank It is obvious that you need a fish tank to set up a home aquarium. 2. An Aquarium Filter No one should keep a fish in captivity without having an aquarium filter running 24/7. To make it clear, fish will die for certain in captivity without a filter. It is just the matter of time. It might be days or weeks, but the fish will eventually die an unnatural death. A filter is for biological filtration. Without it, toxic ammonia released from fish waste and leftover fish food will pollute the water and kill the fish. Make sure you get the right aquarium filter. It is a filter, not a pump. A filter has filter media, unlike a pump which only pumps water. 3. Aquarium Water Conditioner Aquarium water conditioner is required if you use tap water for your aquarium which is more than 99% the scenario. Tap water is the easiest source of water you can use for your home aquarium. However, tap water has chlorine and chloramine in it. Both chemical compounds are harmless to us, but they can and will kill the fish. Aquarium water conditioner can neutralize both chemical compounds and make tap water safe for the fish. 4. Tropical Fish food Like all animals, fish must eat. They also have their special diet requirement. Commercially available fish food is the easiest to use. 5. Live Bacteria seeding Product to establish Aquarium Nitrogen Cycle (for new aquarium) If you are setting up a new aquarium, it is uncycled. Once there is a fish in the fish tank, ammonia is produced continuously. In a well-established aquarium, there are lots of good bacteria feeding on the toxic ammonia. An uncycled aquarium will have ammonia quickly build up and kill the fish. It usually takes weeks to over a month to build up the necessary quantity of good bacteria. In most cases, fish will be long dead before a new aquarium is fully cycled. 6. An aquarium heater Unless you live in a tropical area yourself, you must get an aquarium heater for your aquarium. It will keep the water temperature constant, and it will automatically turn itself off once it has reached the targeted temperature. 10. Aquarium gravel or substrate While most fish can live in a bare bottom aquarium just fine, some fish might become stressed and shy when the bottom of the fish tank is unnatural to them. Some fish species such as corydoras catfish love to dig around the substrate. They do better with fine, soft substrate. It will show their natural behavior. .