Freshwater Aquarium Basics

Welcome to the aquarium hobby! Keeping a tropical freshwater aquarium is a great hobby for young and old, and can be a stepping stone for keeping more complex aquaria. The following is a very basic overview of how to set up and maintain a tropical freshwater aquarium.

Research

The first step before any well-planned aquarium is research. Take the time to think about what kinds of fish you would like to keep. This will determine your aquarium size and what supplies you will need. It will also determine what tank mates you may be able to add in the future.

Aquarium Size

Many beginners start with a 10-gallon aquarium, but as with saltwater aquariums, bigger is better. A larger freshwater ecosystem can better handle the daily fluctuations in water quality than a small ecosystem, absorbing more toxins and reducing stress on the fish. Always be aware of the adult size of some fish and whether or not they are schooling (5 or more).

Setting Up Your Aquarium

You will need good filtration, be it a hang on power filter, a canister filter, or a wet-dry system (for larger or heavily stocked tanks). Be sure there will be adequate bio-filtration to break down fish waste. Check with one of our knowledgeable staff members, as these types vary with the size of aquarium and fish desired.

Substrate or gravel can be any non-reactive stone type. We offer several sizes and colors to choose from. If you wish to keep live plants or a special type of fish (like African cichlids) more specific substrates will be needed. Check with staff if you are not sure which to choose.

A heater is required for all tropical freshwater fish. Most will do best in temperatures ranging from 75-80 degrees Fahrenheit.

Lighting is another requirement, but how much you will need varies. If you are only keeping fish, (no live plants) a simple LED fixture will suffice. Your fish would do just fine without the light, but it will make it easier to appreciate the beauty of your tank. Generally, you do not want to have the light on for more than 6 to 8 hours. If you find that you are having an algae problem in the aquarium, reduce the hours the lighting is on and test your water quality.

Be sure to have test kits on hand to monitor your water chemistry. Liquid test kits are more accurate than test strips. Test the water in your new aquarium at least twice a week for pH, Ammonia, Nitrite, and Nitrate. General Hardness and Carbonate Hardness are also good tests to have available. The pH level in your aquarium should usually be around neutral (7.0), but this may vary depending on the fish you choose to keep.

Cycling Your Aquarium & Adding Fish

Before adding your favorite fish, your tank must “cycle,” or become biologically stable. Cycling is the process where nitrifying bacteria colonize your filter and gravel. This bacteria’s job is to detoxify the wastes created by your fish. You will notice that within the first few weeks by testing your water, ammonia and nitrite levels will rise in the tank and slowly decrease. Also during this time, you may see the water in the aquarium start to cloud or look grey. Don’t worry, this is natural! The cloudiness will pass quickly on its own, or you can add a bacteria supplement such as ‘Stability,’ ‘Nite-Out II,’ or ‘FritzZyme’ to help lower ammonia levels and aid in the cycle. See our guide on Explaining the Nitrogen Cycle for more information on cycling your tank.

We advocate for aquarists to perform what is called a “fishless cycle.” This means allowing the aquarium to fully cycle before any fish are added to help prevent fish death. Since the nitrifying bacteria need a food source, you will want to add a small amount of fish food to the tank to break down into the ammonia that the bacteria eat. Introduce one small pinch of fish food per 20 gallons every two to three days or until ammonia is present. Alternatively, use a liquid ammonia product. Continue to dose the bacteria supplement until ammonia and nitrite levels drop.

While your aquarium is cycling, do not change any water, clean out your filter media, or add more fish. Your tank will be completely cycled when ammonia and nitrite both test at zero and nitrate tests low. This can take anywhere from 3 to 8 weeks. The key here is to be patient and to test your water regularly.

New Fish and Maintenance

When your aquarium is cycled, add new fish gradually. Adding too many fish at once can disrupt your cycle and increase the possibility of fish stress, which can lead to illness or death. Be sure to follow recommended acclimating procedures to ensure a happy addition.

Once cycled, basic aquarium maintenance includes feeding, cleaning, and water changes. When you purchase your new fish, find out what food is best and how often they should be fed. Freshwater foods are available in dried, frozen, and live varieties, and each type of fish has different needs. Cleaning includes scraping aquarium walls to keep them free of algae and siphoning the gravel regularly. Water changes are crucial to keeping your tank healthy. Never change more than 30% of the aquarium water at one time. Changing too much at one time can do much more harm than good. Frequency of water changes varies depending on tank size and stocking level but should be done when nitrates are above 30 ppm to keep nitrate levels low and ensure healthy fish.

With this basic information, you are well on your way to keeping a tropical freshwater aquarium. If you have questions or need help selecting fish or supplies for your aquarium, contact the Fish Room or the sales floor associates. We at That Fish Place - That Pet Place want to keep you and your fish happy for years to come!