How Much Does A 20 Gallon Fish Tank Weigh

A 20 gallon fish tank can weigh approximately 225 lbs. The weight of a fish tank can vary depending on factors such as the amount of rock, thickness of glass, and type of water. The weight of water in the tank can be calculated based on the specific gravity, with each gallon of freshwater weighing approximately 8.34 lbs. If the water has a specific gravity of 1.025, the weight would be approximately 8.5485 lbs per gallon. So, the weight of the water will increase proportionately with the weight of the salt dissolved in it.

How Much Does A 20 Gallon Fish Tank Weigh

How Much Does a 20 Gallon Fish Tank Weigh Empty

The weight of a 20-gallon glass fish tank when empty is approximately 25 pounds. However, the weight may vary slightly depending on the thickness of the tank walls and the specific dimensions of the tank. Acrylic fish tanks of the same size will weigh slightly less than glass tanks.

Glass tanks are more commonly used than acrylic tanks, so it is more likely that you will find a glass fish tank when purchasing a 20-gallon tank.

Is a 20 Gallon Fish Tank a Good Size

A 20 gallon fish tank is considered a good size for many situations. It is considered a medium-sized tank, making it suitable for most fish owners. If you are new to keeping fish, a 20 gallon tank can provide a comfortable and healthy environment for your fish.

Compared to smaller tanks, a 20 gallon tank is easier to clean. The larger size allows for easier access inside the tank, making it easier to clean thoroughly. This can help maintain good water quality and prevent any health issues for your fish.

See Also:  Do Apartments Allow Fish Tanks

Additionally, a 20 gallon tank is less temperamental than smaller tanks. With more water volume, any changes in pH or water cleanliness will have a lesser impact on the overall environment. This can help prevent stress and discomfort for your fish.

How Many Fish Can Live in a 20 Gallon Tank

The number of fish that can live in a 20-gallon tank depends on the size and temperament of the fish. As a general rule, you should provide a gallon of water for each inch of fish to ensure they have enough space to be comfortable.

For example, if you plan to add tetra fish to your tank, which can grow up to 1.5 inches long, you can safely keep up to 13 of them in a 20-gallon tank. However, if you choose to add platies, which can grow up to 3 inches long, it is recommended to keep only 6 or 7 of them to ensure they have enough room.

It’s important to consider the temperament of the fish as well. Some fish, like betta fish, are very territorial and prefer to be alone. Even though betta fish are only about 2 inches long as adults, it is recommended to keep only one male or two to three female betta fish in a 20-gallon tank.

By considering both the size and temperament of the fish, you can determine the appropriate number of fish to keep in your 20-gallon tank to ensure their well-being and happiness.

What Temperature Does a 20 Gallon Fish Tank Need to Be

The ideal temperature for a 20 gallon fish tank depends on the type of fish you plan to keep. Cold water fish, such as goldfish, paradise fish, clown killifish, koi, and dojo loach, prefer water temperatures around 65-70 degrees Fahrenheit. These fish usually do not require a tank heater.

See Also:  How Many Fish Can I Add to a Cycled Tank?

On the other hand, tropical fish thrive in warmer water and typically require a tank heater. Tropical fish, such as betta fish, cherry barb, angelfish, swordtail, and neon tetra, prefer water temperatures ranging from 75-80 degrees Fahrenheit.

Before adding any fish to your 20 gallon fish tank, it’s important to research the specific species to ensure they will thrive in your current setup. Providing the appropriate temperature is crucial for the health and well-being of your fish.


How much gravel do I need for a 20 gallon fish tank?

For a 20 gallon fish tank, you will need to add 20 pounds of gravel. This will provide a layer of gravel that is 1-2 inches thick on the bottom of the tank, allowing your fish to burrow and hide while also providing a place for beneficial bacteria to thrive. Adding too much or too little gravel can cause problems, so it’s important to measure carefully.

How long does it take for a 20 gallon tank to cycle?

It can take anywhere from four to eight weeks for a 20 gallon tank to cycle. Adding established media, such as a used filter, can help speed up the process. It’s important to do daily water changes and monitor ammonia and nitrate levels. To confirm that your tank has fully cycled, you can take a water sample to a fish store for testing. This is crucial before adding new fish to ensure their well-being.

Is a 20-gallon fish tank big?

Yes, a 20-gallon fish tank is considered big enough for most purposes. It is a suitable choice for beginners and offers a variety of options for stocking and decorating. It can easily accommodate all necessary equipment, provide sufficient volume for fish and invertebrates, and is manageable to move around.

See Also:  How Long Do Fish Tanks Last?


In conclusion, the weight of a 20-gallon fish tank can vary depending on the material it is made of, such as glass or acrylic. It is important to consider the weight of the tank, substrate, decorations, and water when setting up a fish tank, as it can have an impact on the supporting surface and transportation.

It is recommended to use a sturdy and level surface to support the weight of the tank, and to place it near a power source and water source for easy maintenance. Additionally, it is important to handle the tank with care when moving it, especially when it is filled with water.

Overall, understanding the weight of a 20-gallon fish tank is essential for proper setup and maintenance to ensure the health and safety of the fish and the longevity of the tank.