Best Affordable Supplies for a 20-Gallon Tank

Kate Barrington
by Kate Barrington

Thinking about getting a home aquarium? You need more than a tank! Here’s our list of best affordable supplies for a 20-gallon tank.

Starting an aquarium requires a certain degree of investment, both time and money. If you’re starting your first tank, it’s a good idea to start with a manageable size – 20 gallons should be about right. Larger tanks are actually easier to maintain than nano tanks, and you shouldn’t have trouble finding affordable equipment for a 20-gallon tank.

In this article, we’ll help you determine what type of equipment you need for a 20-gallon tank. We’ll also show you our top 10 picks for the best equipment at an affordable price.

Related: Best Light Fixtures for a Planted Tank

The Best Affordable Aquarium Supplies

When it comes to equipping your tank, it is important to choose elements that will get the job done. Fortunately, there is plenty of aquarium equipment that is affordably priced and offers decent performance and durability.

Here are our top picks for the best affordable aquarium equipment for a 20-gallon tank:

1. Aqua Clear Fish Tank Filter

2. Aqueon Quietflow Internal Power Filter

The Aqueon QuietFlow internal power filter has a powerful three stage filtration system to remove particles and debris, toxins, odor, and discoloration from your fish tank leaving it clear and beautiful. The first stage is a dense foam to remove debris. Second, it uses activated carbon to remove the toxins, odors, and discoloration. Finally. Stage three is their patented BioGrid technology removes toxic ammonia and nitrates. Even with all that power they are nearly silent as they do all the hard work keeping your tank healthy and clean. They are extremely simple to use and as they are self-priming with a return pipe that gives you the option to mount in the vertical or the horizontal position. The A40 model will fit an aquarium up to 40 gallons! It is a great price point for a thoughtful filter. It is fully submersible and easy to clean by simply replacing the old filter with a new internal power filter cartridge.

3. EHEIM Jager Aquarium Thermostat Heater

3. EHEIM Jager Aquarium Thermostat Heater: This fully submersible heater features a programmable thermostat that allows you to choose the precise temperature for your tank. It comes with an on/off indicator light for at-a-glance monitoring and is made from shock-resistant and shatter-proof glass.

4. FREESEA 25-Watt Submersible Aquarium Heater

If you are looking for a budget-friendly heating option, the FREESEA Submersible Aquarium Heater is a great option. This low-cost heater comes in a variety of sizes, ranging from 25W to 300W. This variety makes it easier to choose the best heater for your tank without overpaying for something larger than you require. The 25W heater is capable of effectively heating and maintaining a 1-to-5-gallon aquarium with a temperature control range from 63F to 95F.

The intelligent temperature design will shut off when the aquarium reaches the desired temperature to reduce the energy required to operate it. If it senses that the water drops below the set temperature, it will automatically turn back on and begin heating again.

In addition to the submersible heater, you will also receive a digital thermometer that will allow you to monitor the temperature of your aquarium at any chosen point in time. If at any time you find that the heater isn’t performing as expected, it is backed by a 12-month warranty and 24-hour professional customer service.

5. Marina Floating Thermometer

5. Marina Floating Thermometer: With a suction-cup attachment, this thermometer is easy to stick to the side of your tank for quick viewing. It includes a safety zone indicator as well, so you can tell at a glance if your tank temperature is within the proper range for tropical fish.

6. NICREW Classic LED Aquarium Light

6. NICREW Classic LED Aquarium Light: Available in a wide range of sizes, this LED light fixture is a great option for beginning aquarium hobbyists. LED lights run cool, so you don’t have to worry about overheating your tank, and they are energy efficient. Plus, this model comes with white and blue LEDs for daylight and moonlight options.

7. API Freshwater Master Test Kit

7. API Freshwater Master Test Kit: Keeping tabs on the water parameters in your tank is important, because even slight changes can affect your fish. This test kit costs a little over $20 to purchase but comes with 7 bottles of testing solutions and 4 reusable glass tubes to help you monitor the 5 most vital water parameters in freshwater tanks.

8. API Tap Water Conditioner

8. API Tap Water Conditioner: This water conditioner comes in a wide range of sizes, so you can choose the one that suits your budget. It is super-concentrated and designed to remove chlorine, chloramines, and heavy metals that could be toxic for your fish.

9. CaribSea Instant Aquarium

9. CaribSea Instant Aquarium: If you’re looking for an aquarium substrate to create a natural look in your tank, this is a great option. It costs a little over $30 for 20 pounds, but you’ll never need to replace it for the life of your aquarium. Plus, it is designed to support biological filtration.

10. Seachem Fluorite Planted Substrate

10. Seachem Fluorite Planted Substrate: If you’re planning on growing live plants in your tank, it’s a good idea to start with a planted tank substrate like this. Simply rinse it in the bag until the water runs clear then add it to your aquarium – you’ll never need to replace it.

If you’re concerned about saving money when building your tank, you may want to think twice. The quality of the equipment you use to run your tank will have a direct impact on the water quality which significantly affects your fish. Consider whether it might be better to save up to buy a better piece of equipment than to rush into something you can’t afford to do at a higher level.

What Aquarium Supplies Do You Need?

An aquarium is a captive environment which means that your fish do everything in the tank. They swim, sleep, eat, and produce waste. Over time, that waste is going to break down and produce byproducts that can be harmful for your fish (like ammonia) – you need certain pieces of aquarium equipment and certain supplies to maintain a healthy and stable tank environment for your fish.

Here is an overview of the supplies you’ll need for a 20-gallon tank:

  • Filter – A filter removes harmful substances and waste products from the water to keep it clean for your fish.
  • Heater – Unless you’re keeping cold-water fish, you’ll need to heat the water in your tank to the proper range for your fish to be healthy and happy.
  • Lighting – For a fish-only tank, lighting is largely aesthetic, but it is essential if you want to grow live plants or corals.
  • Thermometer – If your aquarium heater doesn’t come with a built-in thermometer, you may need one to keep an eye on the temperature in your tank.
  • Test Kit – Different species of aquarium fish have different requirements for things like the pH, hardness, or salinity of your tank water. A test kit will help you track these parameters so you can make adjustments as needed.
  • Water Conditioner – Certain chemicals in tap water like chlorine are toxic for fish, so you need to treat the water to make it safe before you add fish to your tank and any time you change the water.
  • Substrate – To a certain degree, substrate in an aquarium is largely decorative. Depending on the type you choose, however, it can also support biological filtration or plant life.
  • Decorations – Adding decorations to your tank will change the appearance to make it more attractive, but decorations can also give your fish places to hide.

Some of the items on this list are optional, so don’t feel like you have to buy everything at once. You definitely need a high-quality aquarium filter and a heater is recommended as well, but things like lighting and decorations you may be able to wait on.

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Kate Barrington
Kate Barrington

Kate Barrington is the loving owner of two cats (Bagel and Munchkin) and a noisy herd of guinea pigs. Having grown up with golden retrievers, Kate has a great deal of experience with dogs but labels herself a lover of all pets. Having received a Bachelor's degree in English, Kate has combined her love for pets and her passion for writing to create her own freelance writing business, specializing in the pet niche.

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