5 Best 20 Gallon Fish Tank Kits

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When buying a 20-gallon fish tank, there are some important factors that will help you decide which fish tank kit to choose.

Buying a fish tank kit is a great method for beginners as it allows them to buy great 20-gallon fish tanks and they come with all the things necessary to start a tank immediately.

Usually, when you buy a fish tank you then need to consider what kind of filter you will be buying (check out my guide on the best filters for 20 gallons aquariums) and also choose a substrate, a heater (if needed), lighting and the interior decoration.

Luckily, most of these things are already taken into account with fish tank kits, as most of these already contain these important tank parts. All you have to do is then to buy the fish and the decoration for the interior.

But knowing what sort of fish and how many fish you wish to be keeping can prove to be vital when choosing a 20-gallon fish tank for you. All other choices will then depend on that decision.

You also want to make sure that you have enough space for a 20-gallon fish tank at your home. 20-gallon tanks are on the smaller spectrum of aquarium sizes, so it should not take too much space – usually, they come in sizes of 24 inches long, 12 inches wide and 16 inches high.

Once you set everything up and you buy your little aquarium mates, it can be quite satisfying to look at the aquarium and know that it is your own work that you are seeing.

It will, then of course take a lot of dedication from your part to properly maintain the tank, so take that into consideration when buying a 20-gallon tank kit.

If a 20 gallon tank is too big for you or you don’t have enough space, please check out my guide on the 5-gallon aquarium kits. Maybe this article will help you decide what size of aquarium kit to choose.

Let’s take a look at some of the best 20-gallon fish tank kits that you can buy right now.

1. Aqueon LED Aquarium Kit 20H Black

One of the best choices is the aqueon LED aquarium 20-gallon tank kit. It is often recommended for beginners because the package contains almost everything needed for a proper setup. Of course it contains a 20-gallon glass fish tank that is quality-made and conveniently designed.  It has a feeding door that makes feeding the fish much easier.

The kit offers a good filtration system called the QuietFlow 10 LED PRO power filter, that has enhanced five-stage filtration and is also very ecologic – it saves you a lot of energy when it is not required to run. The filter is very convenient for you if you don’t know when to change filter cartridges, as it comes with a red LED light that will tell you when to change the cartridge.

In addition, the LED lighting is also included in the package. The LED lighting is low-profile and it will emit vibrant colors which will imitate the natural habitat of the fish in the best possible manner. Also, a heater comes included which is obviously a great advantage of this kit if you wish to have tropical fish. There is a complete setup guide included that will help you with setting up the tank.

Some other features included in this kit are the premium fish food, water conditioner, fish net and a stick-on thermometer. All in all, this package represents a great deal for beginner fish tank keepers.


2. Marina LED Aquarium Kit

The Marina LED aquarium kit comes in three sizes: 5-gallon, 10-gallon and 20-gallon. But we will focus on the 20-gallon version. It comes in sizes of 24 inches in length, 12,5 inches in width and 16,5 inches in height. Make sure that you have enough space for this tank before buying it.

So what is there included in this package? Firstly, you get a 20-gallon glass aquarium. With it comes a LED lighting system that is already included and incorporated into the aquarium. This system will recreate the natural daylight colors in the best way possible.

Furthermore, you will get a clip-on filtration system that is designed in such a way that you can easily remove it and then change the cartridges quickly. You also get some fish food to start with (Fluval), a water conditioner to turn tap water into the right conditions for the tank, a fish net for the aquarium, some supplements for cleaner water and a guide.

In this kit you will get everything you will need to start your tank (except for the fish, of course).


3. Tetra 20 Gallon Complete Aquarium Kit

The Tetra aquarium kit is also a very complete kit and it includes all the important things you need for an aquarium. The 20-gallon tank is made of glass and it is very sturdy as it is protected from scratches. It has a sleek design and with the right decorations, it will properly imitate the natural habitat.

The LED lighting is also included, and it will produce natural colors. You can change the colors yourself, too. To keep the water clean there will be the Tetra Whisper 20 filter included that will effectively clean the water and will also be quiet.

The package also includes a heater, a digital thermometer and some other features that can be quite useful when setting up the tank – a brochure to help you set it up, a sachet, a fish net and also some other chemicals to help you make the right conditions for the fish.

Consider this package if you want to have a 20-gallon tank and you don’t know where to start.


4. Aq Ascent LED Kit 20g

This 20-gallon tank kit also comes with everything you will ever need for a 20-gallon fish tank.

You will get a glass 20-gallon fish tank, an LED lighting system that is already built-in, a good filtration system that will ensure the quality of water, some fish food and a conditioner.

Aside from the practicality of this kit, the fish tank is also very aesthetically pleasing. So if you are looking for a complete kit with a 20-gallon fish tank, then this would be a good choice.


5. GloFish Aquarium Kit Fish Tank

Another considerable choice would be the GloFish 20-gallon fish tank kit. It would make a great choice, because it also includes everything needed for a good setup and is also of high quality and well-built. The dimensions of the tank are: 24,2 inches in length, 12,5 inches in width and 16,2 inches in height.

Along with the 20-gallon glass aquarium, you will get an LED hood and also an LED light stick that will make sure that the lighting is on point. You will also get a Tetra Whisper 20 filter that will make sure that the water will be well-filtrated and as clean as possible. This will make sure that you will not have to put too much time for maintenance.

Apart from all the essentials, there will be a setup guide included, along with some fish food to get you started, a water conditioner and two plant multipacks. This tank will make for a good choice if you will want to have a colourful and a quality-made fish tank.


Fish Species You Can Keep in 20-Gallon Aquarium

Fish Species for 20 Gallon Aquarium

Fish Species for 20 Gallon Aquarium

After you have chosen the tank kit, you will have to decide which fish you will put in it. Or maybe you have made that choice prior to buying the tank and you adjusted the tank to the fish.

Either way, choosing the right fish for the tank is an important part of creating a good tank environment, and you will also have to consider which fish are compatible with each other.

The guppy fish is one of the most common choices when it comes to smaller tanks. There are plenty of reasons as to why you would want to own guppy fish in your tank.

Firstly, they are very peaceful and will do well in a tank full of other fish. They are not too demanding and very easy to care for. Keep 5 or more of them together to see the best results.

The betta fish is a very popular choice for smaller tanks. This is due to the fact that it is very unique both in temperament and in appearance.

As it is quite an aggressive and territorial fish, it is better that it is kept alone, or at least do not keep two male betta fish together, as they will fight constantly. Other than that, its appearance is very appealing and one of the reasons for keeping the betta fish.

Sparkling gouramis are great little fish for a smaller fish tank. That is due to the fact that they are friendly and non-aggressive to other fish and they will not require too much attention and care from your part.

Some other good fish for a 20-gallon tank are neon tetras, pygmy corydoras, platy fish, balloon molly fish, danios and harlequin rasboras.

Should You Add Live Plants in a 20-Gallon Aquarium?

Live Plants for 20-Gallon Aquarium

Live Plants for 20-Gallon Aquarium

In short, the answer is probably yes, because live plants will create conditions that will resemble the natural habitat conditions, but will also help keep the water clean and will produce oxygen that will keep the fish healthier.

If you are a beginner, it may be better to stick with the plastic plants at first, though. This is due to the fact that live plants can be quite sensitive at the beginning, and will not grow under the right conditions.

But if you want to start with live plants right from the start, please read my absolute beginner’s guide to planted aquarium, which will help you understand how to take care of them.

But live plants are usually better for a 20-gallon tank. Make sure that you clean and rinse them properly prior to putting them into the tank, to get rid of the snails and other bacteria that might be on the plants.

How to Maintain a 20-Gallon Aquarium?

Ideally, you will want to perform maintenance checks every couple of days, if not every day. This will ensure that the conditions of the water are right for the fish and that they are happy and healthy.

When performing these checks, you will want to measure the temperature of the water with a thermometer to make sure that it is in the right zone for the fish in the tank. If you have tropical fish, this is even more important.

Secondly, you will want to clean the tank as much as possible and measure the alkalinity of the water. In addition, you should try to cycle the water at least once a week. This will ensure that the water is clean. To perform a water cycle, change about 30% of the water from your tank with fresh water (dechlorinated with a water conditioner) once a week.

Also remember to feed the fish high-quality foods, but do not overfeed them, as that might cause obesity and an increase in snail population and food leftovers.


Buying a 20-gallon tank is one of the most popular choices for new aspiring tank owners. Fish tank kits make your choice much easier and save you the hassle of having to look for tools and features that are already included in the kit.

All in all, fish tank kits are made with the beginners in mind. Consider these tank kits on this list if you do not know where to start.

Author Image Fabian
I’m Fabian, aquarium fish breeder and founder of this website. I’ve been keeping fish, since I was a kid. On this blog, I share a lot of information about the aquarium hobby and various fish species that I like. Please leave a comment if you have any question.
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