20 Gallon Fish Tanks

So you want to get a fish tank! It’s a very exciting choice.

No matter whether you choose a freshwater or saltwater aquarium, having a fish tank in your space is sure to give you entertainment and peace for many years to come.

However, as you’ve begun shopping and planning for your fish tank, you’ve probably realized that there are more 20 gallon fish tanks out there than you first realized. Which brand? Do you start out with a modestly priced one our pick one of the high quality Aqua One Fish Tanks.

With so many options, how do you choose the right one?

Not to worry. In this article, we’ll provide you with a brief guide to the ten best 20 gallon fish tanks on the market right now.

Read on to discover the fish tank that’s right for you.

1. Aqueon Aquarium Fish Tank 20 Gallon Starter Kit

This starter kit is a great option for beginner fish tank owners. It’s relatively easy to set up and use.

Plus, this tank is equipped with an Aqueon QuietFlow filter that provides filtration in four stages. This helps to ensure crystal clear water for healthy and thriving fish.

The LED system offers white light to illuminate your tank and the kit comes with all kinds of little samples you may need. The Aqueon Team have thought of everything that a beginner would need. They have also included a very handy filter that has a patent pending LED on top which will let you know the perfect time to change the cartridge!

Included in this kit is the

  • 20 Gallon Glass Tank (24-1/4″ x 12-1/2″ x 16-3/4″) Made In USA – Wisconsin
  • LED Lighting
  • Quiet Flow Pro filtration with a medium cartridge
  • 100 Watt heater that will keep your water at a constant 78 degrees
  • Premium Fish Food
  • Water Treatment
  • Small Fish Net
  • Thermometer
Aqueon Background LED Light Kit, 20 gallon
  • Designed With Your Aquatic Pets Safety And Health In Mind
  • Materials Designed In The Usa
  • Quality driven, Competitive Price and Ease of use with Aqueon

Marineland 20 Gallon Fish Tank2. Marineland 20 Gallon LED BIO-Wheel Aquarium Kit

This kit comes with everything you may need to get your 20 gallon fish tanks adventure started.

One of the coolest features is that this tank has LED lighting built into the lid. You can even choose between three different lighting styles, from daylight to cool moonlight.

It can work as a freshwater or saltwater tank, though the lights built in will prevent coral growth if you go the saltwater route.

The stand out features of the Marineland 20 gallon aquarium are

  • Designed for easy access to feed and maintain your fish
  • Energy efficient, Mercury free LED
  • 3 LED Settings – Night Mode – Day Mode – Blue Light Mode
  • The Penguin® BIO-Wheel® Filtration system
  • Lifetime Warranty

More information on their fantastic LED system can be found here.

Marina LED Aquarium Kit, 20 gallon
  • 20 U.S. gallon glass aquarium
  • Includes a Marina Slim S20 clip-on filter with quick-change filter cartridges
  • Includes everything you need to get your aquatic home started
  • Measures: 24" L x 12.5" W x 16.5" H

3. Tetra Twenty Gallon Aquarium Kit

This is one of the coolest 20 gallon fish tanks out there. Plus, Tetra is well known in the fish tank world for reliable quality and great products.

This tank has a Whisper filtration system that will keep your water clean using a three-stage filtration process: filter floss, activated carbon, and Biofoam.

In addition, the ColorFusion model will cycle through different lighting colours or let you choose just one to illuminate your tank.

All Tetra aquariums are made in the USA to the highest standard possible. The Whisper filter is a must have for those who have fish tanks in their bedrooms and struggle to sleep. Everything needed to get started is included with your tank

  • 20 Gallon Glass Tank (24.2″ L x 12.4″ W x 16.7″ H)
  • LED Lighting Built Into The Hood
  • Whisper Quiet Filter
  • Water Treatment
  • TetraMin Food
  • Digital Thermometer
  • Four Artificial Plants Your Fish Will Love
  • Tetra Mini Heater
  • Artificial Wooden Floor Mat
  • Small Fish Net
Tetra Crescent Acrylic Aquarium Kit, Energy Efficient LEDs, 5-Gallon
  • Energy efficient hidden LEDs illuminate your aquarium
  • The Mechanical filter pulls water from the aquarium and pushes it through the filter cartridge where the dense, dual-sided mesh catches debris and waste
  • The Tetra Crescent Acrylic Aquarium Kit uses Ultra Activated carbon for superior removal of odors and discoloration.

4. Marina 20 Gallon LED Aquarium Kit

Marina LED Aquarium Kit, 20 gallon
  • 20 U.S. gallon glass aquarium
  • Includes a Marina Slim S20 clip-on filter with quick-change filter cartridges
  • Includes everything you need to get your aquatic home started
  • Measures: 24" L x 12.5" W x 16.5" H

The LED lighting system in this tank mimics natural daylight, providing a calming atmosphere for both you and your fish.

A clip-on filter makes filter changing easy, and you’ll also receive a fish net and fish food samples in the box.

Another reason people love this tank is that it includes Nutrafin Cycle, which introduces healthy bacteria to your tank without you having to stock it yourself.

5. Marineland (Aquaria) AML11536 Glass Half Moon Shaped Aquarium

Another Marineland tank makes the top ten list. This glass tank is shaped like a half moon, creating a visually appealing way to display your fish.

The seamless 180-degree view you get with this design makes it a common favourite among fish tank enthusiasts. Your fish will swim on by in a sort of bubble-shaped just for your viewing pleasure.

You can customize the lighting of this tank and there is a hole on top of the lid for feeding your fish easily.

6. SeaClear 20 Gallon Acrylic Aquarium Combo Set

This aquarium is extremely easy to get up and running.

The electric fixture that comes with the tank is needed to ensure photosynthesis and proper growth of the aquatic plants in your aquarium.

The beautiful yet simple design of this tank makes it appealing to novice fish tankers and experienced owners alike.

7. Tetra Glofish Aquarium Kit 20 Gallon

The coolest thing about this Tetra tank is the 13-inch Glofish stick. It glows fluorescent and basically throws a rave inside your fish tank.

You and your tropical fish tank residents will be enjoying a hopping glow in the dark party every night as they swim and shimmer under the black light.

The tank also comes with Glofish plants for your tank, like aquatic plants and an anemone, that will truly make your tank design shine. They’ll glow in the dark and really impress anyone who sees your tank.

8. 20 Gallon Long Aquarium

Usually, 20 gallon fish tanks have a square or mostly square shape.

Seeing a long rectangular tank is much less common. However, that’s exactly the appeal of this tank. Because it is 30 inches long, it’s a bit less deep and less wide than most other tanks.

You’ll be able to see your fish easily, because there are fewer places for them to hide in this stretched out tank.

9. CoralLife LED BioCube Starter Kit

Okay, so this tank is just shy of 20 gallons at a mere 16 gallons, but the cool factor far outweighs its slightly lower volume.

The BioCube is a small and uniquely shaped cube like tank that is designed to function as a miniature marine sanctuary. It can maintain an entire reef environment within its four symmetrical walls.

Perhaps the coolest part is the integrated timer. You can program the tank to display a 30-minute sunrise/sunset or a 60-minute moonrise/moonset simulation.

This kit is best for saltwater hobbyists and is a bit more expensive than other starter kits.

10. Fluval Vista Aquarium Kit

This kit is also slightly off of the 20 gallon mark at 23 gallons, but its seamless sweeping design makes it one of the most loved tanks out there.

The built-in lighting system consists of a soft start lamp that takes some time to reach full brightness. This slow progression helps to minimize the initial light shock of the day to your fish.

The tank also comes with a heater and thermometer, and is recommended for freshwater use only.

Twenty gallon fish tanks are an excellent choice for new aquarium owners. Easier to maintain than smaller tanks, 20 gallon fish tanks provide enough space to accommodate a variety of interesting fish species.

Keeping water quality consistent is often easier in a 20 gallon fish tank than in a smaller sized tank. These tanks come in a range of shapes and designs, which means you can select a tank that can fit easily into the space you have available for your home aquarium.

Picking a Good 20 Gallon Fish Tank

Before you select a 20 gallon aqua one aquarium for your home, think carefully about where you will locate the aquarium. This will dictate the shape of tank that suits you best. Remember, you do not have to stick with traditional rectangular fish tanks. You can also select a tall fish tank to slot into a narrow gap. Some 20 gallon tanks are curved, which means you can have even more flexibility when selecting the perfect tank for your home.

Both glass and acrylic 20 gallon fish tanks are available. Acrylic is a type of plastic that is much lighter than glass and can be used to make tanks in a much greater range of shapes compared to glass. The main disadvantage of acrylic is that it scratches easily, whereas glass resists scratching. Acrylic tanks are also typically more expensive than glass tanks.

Setting Up Your 20 Gallon Fish Tank

Many 20 gallon fish tanks come in a complete kit which contains everything you will need to set up the tank and begin your life as a proud aquarium owner. If you buy a 20 gallon aquarium kit, all you need to do is follow the instructions to get your fish tank set up.

If you buy a standalone 20 gallon fish tank, you will also need to buy support equipment before you can use the tank. Essential support components include a suitable filtration system, appropriate lighting, and a water heater. Tropical fish thrive in temperatures of between 24 and 27 degrees centigrade, so you will need a heater that can provide this much heat.

In addition to support equipment, you will probably also want some accessories for your 20 gallon fish tank. For example, you will need gravel to line the bottom of the tank, plants to help clean the water and provide oxygen for your fish, and ornaments to create an interesting environment.

Before setting up your fish tank, it is a good idea to rinse everything that you plan to place inside it, including the gravel. Use plain water with no soap or detergent—these are toxic to fish.

Once all your materials are clean, put the gravel into the tank. Use a plate or saucer to weigh the gravel down, and then pour water onto the plate or saucer until the tank is about one third full. Next, hook up the airlines and other equipment, and arrange the ornaments and plants in your tank in a way that looks pleasing.

Finish filling the tank but leave the lid off. You now need to leave the tank for three days before you can add fish. During this time, chlorine in the water will naturally gas off, leaving the water safe for your fish to live in.

Best Fish for a 20 Gallon Fish Tank

Twenty gallon fish tanks make good homes for freshwater fish such as guppies, platies, and neon tetras. You can also add some bottom feeding fish, such as cory catfish and bristlenose catfish. These fish are all quite hardy and good for beginners, including children, to look after.

If you choose to stock your tank with colorful neon tetras, be sure to purchase at least five or six individuals, as these fish feel most comfortable in the company of their own species. In the wild, neon tetras live in schools of thousands of fish.

Avoid selecting any fish that are too large or too aggressive for your 20 gallon fish tank. Some people try to keep tiger barbs in 20 gallon tanks, but these aggressive fish can nip the fins of other species. They are really only suitable for tanks of 30 gallons or larger.

Maintaining a 20 Gallon Fish Tank

In order to keep your fish healthy, you will need to keep your tank clean and ensure that the water quality remains sufficiently high at all times. Before you add fish to the tank, it is a good idea to use testing strips to check the pH and nitrogen levels of the water. Ensure that the test results you achieve match the living conditions of your chosen fish. You will need to repeat these tests regularly. For example, you can do them during your regular water change process.

Once your tank is set up and your fish are happily swimming around, you can begin your regular maintenance schedule. Roughly once every two weeks, you need to replace roughly 10-15% of the water in the tank to keep it clean. You should also vacuum the gravel during this time to remove uneaten food residue and other waste. Rinse your filter inserts and clean the aquarium walls with filter floss.

Simply watching your fish feed can be a good way of checking up on the health of your tank. Look for behavioral changes, such as aggression, floating, or fish swimming on their sides. These can indicate health problems, which may result from non-optimal conditions in your tank. Also, be sure to count your fish—if any die and go unnoticed, they may quickly decompose, causing nitrite levels to spike.

By paying careful attention to your 20 gallon fish tank, you can be sure that it will provide a healthy environment in which your fish can thrive. This size of tank is perfect for beginners, including kids, to get their first taste of aquarium ownership. Choose your tank today so you can get started with the fun task of selecting fish with which to stock it

The Best 20 Gallon Fish Tanks and More

If you’re on the hunt for the perfect 20 gallon fish tanks for you, we have good news.

On this site, we can answer that. You’ll also find everything you ever wanted to know about the care and keeping of a marvelous fish tank.

From cleaning tips to fish tank reviews, we’ve got you covered.

Now that we’ve got that handled, we want to hear about your fish tank experience. Have you tried any of the 20 gallon fish tanks listed above? How’d you like them?

Let us know in the comments below!

Last update on 2020-04-04 / Affiliate links / Images from Amazon Product Advertising API