If you want the fish in your saltwater aquarium to survive, you must know how to maintain and clean the aquarium. Maintaining your saltwater aquarium involves carefully monitoring the following:

  • Temperature Make sure the tank's temperature is maintained between 73 and 82 degrees Fahrenheit (23 and 28 degrees Celsius). Seawater fish thrive in those temperatures.
  • Salinity Make sure the proper amount of salt is dissolved in the water. Salinity is measured in parts per 1,000 units of water. The ocean's salinity is about 34 to 37 parts per 1,000 units of water. Your aquarium's salinity should be as close to this as possible. You can measure your aquarium's salinity with a refractometer or hydrometer. These can be purchased at most pet supply shops.
  • pH Make sure the water has the proper pH level. pH is the measure of the amount of acid or alkali in water. You can measure the pH level with color-coded testing strips that can be purchased at most pet supply shops [source: Sea World].

Cleaning a saltwater aquarium involves cleaning the water and the contents of the aquarium after temporarily re-housing the fish. Here's what to do:

  1. Remove sufficient bottom material from the tank to fill a bucket one-third full.
  2. Flush the bottom material with fresh water, by filling the bucket with fresh water.
  3. Mix the water around with a stick as it's filling the bucket. Avoid mixing the water with your hands, as there may be sharp items in the sand. While you're mixing, dirt will float to the top and spill out of the bucket.
  4. Pour the water out of the bucket as soon as you see that it's clear.
  5. Spread the bottom material on a flat area to dry it out.
  6. Repeat the process until everything from the aquarium has been removed and cleaned.Clean the walls of the aquarium while everything from the aquarium is drying.
  7. Fill the tank with fresh salt water.
  8. Clean the aquarium's water whenever it doesn't look clear and has a bit of a bad smell. Simply siphon off a quarter of the water in the tank and replace it with a new batch of salt water [source: University of Florida].