How to Put Together a Saltwater Fish Tank

Choose your aquarium size. You should start with a minimum of a 15-gallon tank. The larger the tank, the easier it will be to maintain. Research the size fish you want to determine the size tank you will need.

Rinse out your tank with water. Avoid soaps or other cleaning agents because the residue they can leave behind will hurt your fish. It is also a good idea to check the tank for any leaks at this stage. Fill the tank with water and watch it for a few minutes to ensure there are no slow leaks.

Place your aquarium on a stand that is made for its size and potential weight. If you are in doubt about the stand, check with an employee at your local pet store or fish supply store. Place the aquarium and stand in a location where sunlight or heating and air vents will not directly impact your tank's temperature or light.

Apply a background to the outside of the tank if you want. Use tape to adhere the entire top of the background to the tank. This helps prevent salt from getting between the background and the tank. Or paint the outside back of the tank with a dark color. If you choose to paint, allow it to dry for a full day before proceeding.

Install all equipment according to package directions. You need a heater, filter and protein skimmer. For the filter, avoid under-gravel filters. They are not necessary, especially if you use live rocks in your tank.

Pre-treat your water by filling a 5-gallon bucket with room temperature tap water. Add a store-bought additive that removes chlorine and chloramines. Follow the package directions. Add your chosen salt mix according to package directions. Salt mixes can be found at pet supply stores. Stir the mixture using a hydrometer, which allows you to read the specific gravity, or density, of the water. You want a reading of 1.021 to 1.024.

Add the mixed water to your tank. Repeat Steps 6 and 7 until your tank is filled.

Plug in the filter, heater and protein skimmer. Allow them to run for a full day before proceeding.

Place live rock in your tank. The type and size of rock is up to you. Place it in the center of your tank and point all the power heads from the filter toward the rock. This will cause the power heads to blow off debris from your rock, which you can siphon off with a tank siphon.

Every 4 to 5 days, turn off the filter and protein skimmer. Rub the surface of your rock using a toothbrush to remove any dead or dying organisms. Use your siphon to remove the debris. Replace the siphoned water with premixed water that is mixed in the same method as in Step 6. The only difference is that it should be mixed a day in advance to ensure it is at the proper specific gravity before adding it back to the tank.

Repeat Step 10 until your tank as no ammonia, no nitrites and at least a small reading on nitrates. This can take several weeks. Usually, your tank will smell until you reach these readings.

Fill a 5-gallon bucket with water and salt mix as in Step 6. Add the sand you want to use for your tank into the bucket, and stir it up. Siphon off any debris that is stirred up. Use a plastic cup to add the sand to the base of your tank. If sand ends up on your rocks, use the power heads to blow it free. If necessary, remove a few inches of water from the tank to adjust for the water to be added.

Leave your tank for 3 to 4 days until the temperature is 75 to 80 degrees Fahrenheit, the specific gravity is 1.020 to 1.024, the pH is 8.0 to 8.4, the ammonia and nitrites are at 0, the nitrate is at 20 ppm or less, and the carbonate hardness is 7 to 10 DkH. These can be tested with test kits you can purchase at your local pet store.

Add one to two fish to your tank at a time. Put the fish and the contents of the bag it came in into a 5-gallon bucket with a cup of water from your aquarium. Add another cup of aquarium water every 10 minutes for an hour. Add the fish to your tank, but not the water from the bucket. Do not feed the fish on the first day. Wait a few days before adding additional fish.