The Best 20 Gallon Fish Tanks for 2021


What are the best 20 gallon fish tanks? If you’re new to aquascaping and setting up an aquarium, you might be interested to know what the right 20-gallon fish tank for you is.  It can help you get started in the new hobby and to complete the setup of your tank with ease, especially if buying a complete kit.

However, it can be time-consuming to research and compare your options without an idea on what this tank is, how many fishes can fit it and how much it weighs approximately. It can also be stressful to choose one without knowing the factors to think about when comparing different tanks.

Let us answer all those questions and highlight a buying guide for help. Also, have an idea on the best products and their pros and cons in the following reviews.

What is the Best 20 Gallon Fish Tank for 2021

Top 6 Best 20 Gallon Fish Tanks Reviews

1. Tetra Deluxe Aquatic Turtle Kit 20-Gallon


The Tetra Deluxe Aquatic Turtle Kit is a good pick in this category because it is loaded with the features that aquarists and hobbyists are looking for in a tank. The kit comes with the accessories to start with the setup.

Now, you can take away your worries about the new hobby being stressful.  You can also ensure that you are going to give your turtles or new pet a great environment. This item includes the essentials including a basking platform as well as a waterfall filter.

It also has a basking platform for your reptiles as well as elegant design for improving the aesthetics of any room.  Tetra Deluxe Aquatic Turtle Kit is overall a good choice for a 20-gallon aquarium. Take a look at it if you’re looking for lovely looking terrarium that creates a nice focal point in any room.


  • Can improve home’s decoration
  • Lovely terrarium
  • Decorative ReptoFilter
  • Warmth with the two dome lamps
  • Includes accessories


  • Filter can be noisy

2. SeaClear Acrylic Aquarium Combo Set 20 gal Rectangular


SeaClear Acrylic Aquarium Combo Set is a top-rated choice for many who want a reliable aquarium kit to start with in setting up a tank.  It is a high quality choice that is a top-rated one among many that want to get started and to keep an aquarium.

This item includes a reflector, aquarium and light fixture. It is also clearer and lighter than glass is. You might want to check it out if you want to get started fast.

It is also stronger than glass is, so it is preferred by more aquarists. While it is lighter in weight, it can give you heavy-duty performance.  The combo is also impact resistant, adding to its durability. It is also safer to have around pets and children because it is less prone to chipping than glass, too.


  • Complete combo for quick set up
  • Easy to install
  • Made of premium and impact resistant materials
  • Safer to use than glass
  • Beautiful focal point for a room


  • A bit pricey

3. Marina LED Aquarium Kit 20 gallon


Marina LED Aquariums are known for their quality and durability. They can last long and give you more value for your money.  One of their best offerings is the 20-gallon tank kit that has all the things that you need to set up.

The 20-gallon glass aquarium is ideal for a novice aquarist that wants nothing but the best. This model comes with a clip on filter to help maintaining the cleanliness of the water. It also has a LED lighting module that provides a natural daylight effect.

In addition, it comes with a water conditioner that can keep the water safe for your tank friends. Finally, it includes a soft mesh made fish net that can protect the fish’s sensitive fins.


  • Natural daylight effect LED
  • Includes S20 clip on filter
  • Ideal for novice
  • Comes with a water conditioner
  • Comes with advice to install and maintain


  • Can be prone to chipping

4. Tetra 20 Gallon Complete Aquarium Kit


If you’re looking for a complete kit, you might want the Tetra 20 Gallon Complete Aquarium Kit. It includes all the things you need to set up the tank quickly even if you’re a novice.

The complete kit set comes with artificial plants and decorations, so you don’t have to buy them separately. It also comes with one piece of white anemone that adds more beauty to your tank and that gives your pets a hiding place where they can relax.

This model also comes with a LED lighting that can transform things every time it changes color.  Under it, the tetra plants can come to life, too! The only things you need are care items, fish and gravel or any other substrate of your choice.


  • Universal Color Changing LED
  • Plastic plants and decoration
  • UL heater
  • Includes a white anemone
  • Ideal for novice aquarists


  • Filter can stop working suddenly

5. GloFish Aquarium Kit


Do not miss this kit if you want a quality and heavy-duty set that can give you more value for your spending.  It comes with needed filtration and LED lighting.  Both are essential in setting up your tank.

The 20-gallon tank is one of the best choices for those looking for an effective filtration system.  It can keep the water clean for the health of your tank friends.  It works by keeping the water clear and provide a nice environment for your pets.

In addition, this item comes with a blue LED light that can transform your tank and make it looking livelier.

The GloFish Aquarium Kit is with premium components for long-term use, too. It also comes with two plant multipacks, water conditioner sample and fish food, allowing you to get started quickly even if you’re a beginner.


  • Environment-transforming LED light
  • Complete kit for easy setup
  • Effective filtration
  • Novice-friendly
  • Quality materials


  • Filter can be noisy

6. Amphibian or Reptile Tank 20 Gallon


Do you already have accessories for your tank? Or do you just need a tank for your reptile, amphibian or fish?  If so, you might be looking for a reliable tank that can last long and does not chip easily.

This product is made of durable materials, so it is less prone to breaking and chipping than other products are. It can also offer a nice focal point to any room because it is clear that people can easily see what’s inside the tank.

In addition, the 20-gallon tank can offer more room to your pets versus the 10-gallon tank does (if with the same components inside the tank). This item is also beginner-friendly because it is easy to set up and gives you plenty of options to decorate and set up the tank.


  • Affordable and quality materials
  • Durable and heavy-duty construction
  • Ideal for those already with the other tank essentials
  • Easy to clean and maintain
  • Safe to have around with pets and children


  • Some reports of receiving a different product

20 Gallon Fish Tank Buying Guide

There are certain things to look into if you want to find a good 20-gallon fish tank for your home. However, if you’re new to this hobby, you might be feeling overwhelmed with the plenty of choices to find in local shops and online stores. For this reason, you might be thinking about the essentials to consider when comparing your choices. Here is help.


Do you have space for the aquarium? Take note of the dimensions of the 20-gallon tank.  More so, you have to consider if you have enough space for tank as well as a sturdy area to install it.

Types of fish

What fish will you keep? It matters when shopping around for a fish tank because its size matters for these creatures.  For this reason, you should research as much of the types of fish to keep in the tank.

Know how large they grow and find out if they will have enough room to grow in the aquarium.   If you don’t buy the right size of tank, you might have to buy a new one sooner.  It will waste money in the end, so it matters to find the correct size for the types of fish to buy.  The same is true especially if you want only the 20-gallon tank.

Number of fishes

In addition to the type of fish, you must also think about the number of fishes to keep in the tank. The general rule is a gallon of water for every inch of the full-grown fish. It is why it pays off to research before buying a tank.

Remember, the 20-gallon tank doesn’t mean that you will only have water in the tank. Who can keep a tank without filtration, plants or absolutely nothing?  Of course, there are live pets, decoration, substrate, heater and other accessories, too.

What is a 20-Gallon Fish Tank?


This tank is much bigger than other beginner tanks like the 10-gallon tanks are.    It is also a common choice among novice hobbyists that want an easy to set up and keep aquarium. It can hold different types of aquatic animals like fish or turtles.  If you’re looking for this type of tank, you can get started in our reviews earlier.

Types of  20 Gallon Fish Tank

If you’re planning to buy this fish tank, you should know their types. At the very least, the types are based on the material of which the tank is made.  A freshwater tank can be glass or acrylic. The prior weighs as much as 177 pounds and the other 167 pounds.

For a saltwater tank, a glass one can weigh 181 pounds and an acrylic 171 pounds.  But it’s just a quick overview based on the weight of the tank per type of material.

Now if you’re asking which to choose, it can be a personal preference. But more often than not, glass is a common choice for many. It is maintain and care for especially among beginners.   It does not scratch easily, but its edges can chip. It is also heavier than acrylic is.  This tank only needs support along the outside edges.

There are also acrylic aquariums that are lightweight, do not chip, and have smooth corners.  These tanks also have less distorted view than a glass can offer.   However, acrylic can be easily scratched and needs a stand plus support for the entire bottom’s length.

Nevertheless, these are only some of the differences of 20-gallon fish tanks based on materials. You can start comparing your choices according to the pros and cons of each material. Also, you can think about your budget and types of fish you want to keep in the tank. In addition, consider your space and the readiness of a sturdy support, as each tank needs a stable one.

Why Do You Need 20 Gallon Fish Tank?

What are the benefits of a 20-gallon fish tank? Here are some reasons.

Space –  You need a 20-gallon fish tank that allows a much more room for your pet fishes than a 10-gallon tank. It is also yours if you want a more sustainable sized tank that will accommodate more fishes than a smaller tank can.  It allows more space and room for your pets to move and grow.

Options to decorate – A bigger tank like it can handle more decorations, such as fake plants and other accessories than a smaller one can.  It might be what you need if you want to explore your creativity and try to add more decorations to your tank.

Environment – With more options to decorate, you’ll be able to create the kind of environment you want for your pets.   For sure, you can make them happier and feeling less stressed.

However, make sure not to overcrowd the tank, as it can also affect the health of your tank friends as well as your tank’s entire suitability for your pets.

Definitely, there are more benefits to having a 20-gallon tank that you need to know. The above is just a brief overview of the things to know about the reasons to have this tank.

Frequently Asked Questions

FAQs-fishHow many fish in a 20 gallon tank?

Aside from the type of fish to keep, you should also know the number of fish for this tank.   The very basic rule is a gallon of water for every inch of the adult full-grown fish.

As said earlier, having a 20-gallon tank doesn’t mean 20 gallons of water because you will also need to set it up with substrates, filter and other accessories/equipment.  It only means that you will not really end up with 20 gallons of water.

Just ensure that there will be enough room for the fish to thrive in the tank, or else, a very crowded tank will make them sick.

How much does a 20 gallon fish tank weigh?

Generally, the 20-gallon fish tank will measure 24 x 13 x 16 inches overall.  With this size, a glass tank will weigh about 177 pounds if you are going to fill it with freshwater, but 181 if filled with saltwater.  On the other hand, an acrylic tank will weigh 167 pounds with freshwater and 171 with saltwater.

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

In addition to those questions, you may be asking about the amount of gravel you can put in a tank of this size.  At the very least, it is one pound for every gallon of water. It only means that this tank size will need about 20 pounds of substrate like gravel.

Where to buy 20 gallon fish tank?

You can buy this tank in fish/pet supplies stores as well as online marketplaces like  For many, they go to Amazon where they can find the best deals and quality tanks.  Here, they can also buy from the manufacturers themselves, ensuring buying only legitimate tanks that have the durability and quality that they need.


There you have what to know about the best 20 gallon fish tanks, which can offer more room to grow and move for your tank friends than smaller ones can.   These tanks are durable and quality and are by reputable manufacturers.

Most of them are complete kits that have all the accessories you need for setting up. That said you could rest assured that you’d be able to get started with your new hobby.  However, make sure that you spend effort and time in comparing and weighing your options well. You can get started referring to our guide highlighting the top picks in the category for help today!

2 thoughts on “The Best 20 Gallon Fish Tanks for 2021”

  1. Your article is complete and helpful to me. I like the way you list the pros and cons of each type of fish tank. Thank you, I will continue to monitor your posts

  2. I’m really appreciate about the LED lighting of Marina LED Aquarium Kit 20 gallon . It’s very cool the eyes, it is neither glaring nor dim. Another exciting feature of this tank kit is the heater which can prevent my mollies from freezing during the winter season.
    However, there is one thing that I wish I had known before buying it! The filter is not completely silent so if you want to put this tank in the bedroom, please take this in to consideration.


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