Before you place fish into your saltwater aquarium, clean the aquarium and the area where you will set the tank. You can clean your tank with diluted bleach (one teaspoon of bleach and five gallons of water) as long as you thoroughly rinse the aquarium afterwards. Place your aquarium in a common area, near an electrical outlet and away from direct sunlight.
Next, install the aquarium’s filtration system (the best filters offer biological, chemical, and mechanical filtration) according to the owner’s manual and lay aquarium gravel inside the tank. You’ll also want to install a heater, air pump or powerhead, and protein skimmer, and to keep a chemical test kit on hand. Finally, don’t forget the fun and colorful supplies, such as plants, hideouts, and large rocks. Have fun decorating your tank, and just make sure that nothing in your tank is made of metal, as metal objects will rust.
The only other thing you need is the saltwater, and all you need for that is water, salt, and a hydrometer. Gradually mix salt into dechlorinated water (approximately ½ cup of salt per gallon of water) until the hydrometer displays a salinity reading between 1.020 and 1.025.