Freshwater Versus Saltwater Aquariums: What You Need to Know

6 min read


The Equipment


A tank, preferably with a hood, substrate for the bottom (like gravel or sand) and a filter that can process the water five to ten times per hour are required for both freshwater and saltwater aquariums.


With regards to the size of your tank, your level of interest can dictate the size of your freshwater tank. From housing a single betta fish in a one- gallon tank to a 350-gallon show tank, there are plenty of options. You will also need a cover above the tank to prevent rapid evaporation. If you choose to house plants or you would like to see the fish at night, you will need to add a light. An air pump to add oxygen and a heater/thermometer to monitor the temperature are also required with freshwater tanks.


A saltwater tank should be at least 30 gallons for best results. Small fluctuations in water quality are amplified in smaller tanks, making them difficult for housing a marine system. In addition to the components for freshwater aquariums, most hobbyists recommend a protein skimmer for saltwater tanks to remove organic wastes. The protein skimmer works in conjunction with the filter and will need to be emptied and cleaned about once per week, depending on the size aquarium and number of inhabitants.


Corals in saltwater tanks have special lighting requirements with regard to the intensity of the light and the number of hours of lighting. There are a variety of lighting options, some with automated light cycles to mimic natural sunlight. A substrate that many hobbyists include in their saltwater tanks is live rock, a porous rock that is inhabited by microscopic organisms including algae and bacteria that will benefit your tank. Rock is sold per pound and can be used as a base for corals and anemones.


The Costs


The cost of freshwater fauna can be very reasonable, with varieties of common fish selling for a little as five dollars. Some of the larger and more ornate fish, like plecos and koi, can be several hundred dollars and are recommended for more experienced aquarists. Building a freshwater aquarium does not have to cost a lot of money. You can start modestly with a ten- gallon tank that is often packaged with a hood, filter and gravel for under 50 dollars. Maintaining a freshwater aquarium does not have to be very time consuming, as most freshwater fish are relatively hardy and forgiving of the mistakes made by new tank owners. With a small investment, a newcomer can build on to the tank as their interest in the hobby grows.


Marine aquariums, however, are an investment in money and time. More equipment is needed for a marine set-up and it is significantly pricier (hundreds to thousands of dollars). Saltwater livestock is considerably higher in cost than freshwater. While there are some fish priced below 20 dollars, most saltwater fish are priced at 50 dollars and up. If owning a saltwater aquarium is something that you are contemplating, be sure to do extensive research and find an experienced hobbyist who is willing to offer advice while you get your feet wet.