Last updated: September 3, 2021

Having a fish tank at home will beautifully decorate your living space. As soon as your guests arrive, their eyes will be attracted to the colours that radiate from it, discovering healthy fish swimming freely through the waters. You have to know that you need to pay attention to fish if you get a tank. While you may have thought otherwise, fish should be cared for every day.

Here is our ultimate guide on fish tanks: the best models on the market, the answers to the most frequently asked questions about these accessories, and the criteria to pay attention to when buying your very own. You'll learn everything there is to know to make the right purchase. Whether you're getting your first fish or already have these wonderful creatures in your home, this guide is ideal for you.

Key Facts

  • A fish tank is the most important accessory you'll need for your fish. You need to buy the best possible model If you want your pets to live happily in your home.
  • Many different types of fish tanks are available on the market: for salt water, fresh water, and warm or cold water. Experts encourage fishkeeping newbies to start with cold water fish, such as goldfish. This is because it is easier to maintain water cold than warm.
  • Purchasing your fish tank is the first step in having these animals at home. You'll also need filters, decorations and anti-chlorine treatment, amongst others. Our article will focus on the different types of fish tanks at your disposal.

Our selection: The best fish tanks

It is important that you provide your fish with a comfortable home and lifestyle if you want them in good health. This is why buying the right fish tank is fundamental. In the following section, we've listed the best models available on the market right now. That way, you can choose the most suitable fish tank for your home.

Shopping Guide: Everything you should know about fish tanks

The section below will answer most of the questions you may be asking yourself regarding fish tanks. You'll learn everything you need to know to make an informed decision when the time comes to buy your own. As you probably know, each fish has specific needs, although several species can also cohabit in the same tank.

Girl With Sales Assistant Choosing Goldfish In Pet Store

Rectangular fish tanks are ideal because their shape makes them easy to place in homes.
(Source: Ian Allenden: 45008525/

What is a fish tank and what are its advantages?

A fish tank is a container mostly made from glass and plastic. It is designed to reproduce the environmental conditions of the fish habitat. You can also add various items and accessories for your pets in this artificial body of water. These include water filters, purifiers, heaters, gravel, sand and other decorative objects.

Nowadays, you can find fish tanks in millions of homes around the world. Many people love to have fish and take care of them. However, it is essential to keep them in the best conditions possible. This means that you need as much information as possible regarding cleaning, maintenance and solving various problems that may arise.

Good news: fish tanks aren't just for your house. They can also be found in offices, residences or any other place where someone can take care of their maintenance. Here is a useful list of the advantages of having a fish tank in these different places:

Advantages of fish tanks: It is a small natural space in your home or office. Observing a fish tank and being aware of the peace in which fish live is almost a form of meditation. This will calm you down and reduce the levels of stress to which you are subjected every day.

Fishkeeping is a very healthy pastime where you are not alone. While fish cannot be compared to dogs or cats in many ways, they are with you and you can create a very strong bond. Remember that the bigger your fish community is, the more entertaining your fish tank will be.

How should I clean my fish tank?

Although you can postpone that moment using water purifiers and anti-chlorine treatments, you should always try to keep your fish tank clean. You need to learn how to do this correctly, otherwise you may face a series of different problems. We've designed the following step-by-step instructions to help you get it right:

  • Remove the excess dirt from the fish tank once a week. To do this, you have to change 25% of the water using a siphon. That way, you can suck up the gravel waste while preventing the filter from getting clogged. You should naturally use water that doesn't contain any detergent or other product that can be toxic for your fish.
  • Algae tend to proliferate when powerful lighting and poor water quality are combined. That viscous green material will adhere to the glass, to the decorative objects and at the bottom of the tank. The most appropriate way to remove this dirt from the panes is using a scraper.
  • As for the decorations, you can put them in water with bleach. Avoid using soap or detergents. Rinse them thoroughly before putting them back in your fish tank.
  • The next step is cleaning the filter, which we'll look into more details in the following part.

Can fish tanks self-clean?

This is the ultimate wish of many a fish owner. Since the regular maintenance required by fish tanks can be somewhat wearisome, people have used their ingenuity to design and create self-cleaning models. A good solution is, for instance, to opt for a fish tank that features a small garden on top.

The process is quite simple: the system is built in such a way that the fish excrements can be used as fertiliser for the plants. At the same time, those plants also take care of filtering the impurities from the water. This solution is incredible, but unfortunately these products tend to be very expensive.

goldfish in the aquarium water close up

You can find fish tanks that come with all the accessories and decorations included.
(Source: Dmitry Maslov: 54595713/

How can I remove the lime from my fish tank?

In addition to dirt such as algae or excrements, your fish tank may also accumulate a thin white layer of lime or rust. This situation often leaves fish owners scratching their heads. But first of all, relax: this problem sip purely aesthetic and is not toxic for your pets.

This substance is made up of the remains of minerals and alkaline substances in the water. In order to find a solution to this problem, you should start by removing your fish and placing them in another space. Once you've done this, you can rub the glass of the fish tank with a double-sided sponge (like the ones used in the kitchen) with hydrochloric acid or vinegar. Throw the sponge out after use.

How should I decorate my fish tank?

Many people want to know the answer to this question, because a tank with a single fish can look quite sad. You have three decorative options on hand to avoid this little problem: plants (thin-leaf, large and dark), rocks (try to use round ones, without sharp edges to prevent harming your fish) and coloured sands.

In addition, many manufacturers of fish tank decorations sell adhesive images to stick on the glass of the tank, statuettes and accessories that imitate sunken ships. You have access to a wide array of items and products to create the atmosphere you want, and you can play around with these options so that your fish have a wonderful tank to live in. Play with light and dark areas to give a feeling of depth to your tank.

Did you know that most fish actually do have a memory? That's why some carp don't bite the same hook twice.

What types of fish tanks are available out there?

These essential accessories aren't just a glass container filled with water. You need to be aware of the characteristics of the fish you have (or want to have), so that you can equip the fish tank with everything your pet needs. Your main goal is to imitate, as faithfully as possible, the natural habitat of this species.

In the following table, we've listed the main types of fish tanks available on the market to help you choose the most suitable model. You should evaluate the water composition, the origin of your fish, the temperature to which it is accustomed to live and the plants that make up its habitat to determine which of the fish tanks below is most appropriate.

Types of fish tanks Characteristics
Tropical freshwater They reproduce the habitat of tropical river fish from around the world.
Cold water They are the simplest and ideal for fishkeeping beginners. They need a good filtration system and should be big enough, because goldfish — the cold water fish par excellence — tend to grow a lot.
Tropical saltwater  More beautiful, they tend to boast more colour but are harder to upkeep. These fish tanks generally host fish that aren't used to living in captivity, so recreating their habitat is more complex.
Dutch style  Tropical freshwater fish tanks where flora (plants) is given more importance than fauna (aquatic animals).
Paludarium  Also called aqua-terrarium, they reproduce humid habitats and tropical and swamp regions ideal for reptiles, amphibians and certain types of fish.

What are the basic accessories my fish tank needs?

It's important to have a list of the essentials if you want to create a fish tank that is both fully functional and beautiful. If you go in thinking that only decorative items matter, you're dead wrong. Here are four accessories that you absolutely must buy for your fish tank or aquarium:

  • Water filters. As the name suggests, they filter and purify the water. They have one other very important function: achieving balance in the fish tank ecosystem, due to the bacteria generated by the residues accumulated by the filter.
  • Aerators. Providing the right quantity of oxygen to the fish tank is fundamental, because it allows your fish to live peacefully in their habitat. Since this water system is closed, the ideal solution is to eradicate oxygen particles so that your pets can breathe.
  • Lights. In reality, they are more important for your plants than for your fish. Plants will broaden if you have a lot of light, and they'll stretch to look for it in case there is little. In any case, you should always prevent direct sunlight from hitting your fish tank.
  • Water testing. You should regularly test the fish tank water to make sure that it is in perfect condition. This will also increase the life expectancy of your fish.

What is a filter for fish tanks?

This device is essential for the correct maintenance of your aquarium, as it is responsible for recirculating the tank water, filtering the debris and toxic components generated by the flora and fauna of the aquatic habitat. Filters aren't required in natural systems (such as lakes or rivers), but they are in fish tanks where the water stagnates.

Filters are designed to simulate the natural conditions of the aquatic environment. This is why you need to set one up in your fish tank, as it will help find the right water composition balance. Many fish owners ask themselves one question: Can the filter ever be unplugged? The answer is no, in particular when it needs to be cleaned.

Little happy boy holding a plastic bag with new fishes he bought at the zoo store for his home room aquarium feeding and taking care of pets

Filters are designed to simulate the natural conditions of the aquatic environment.
(Source: Famveldman: 31615572/

How does the filtration mechanism work?

While several types of filters exist, their use tends to be similar and quite simple. This is because all filtering devices contain the same parts: a water pump, a filter chamber (generally found in more advanced models), and a water inlet and outlet. Now that you know its different parts, here is how exactly a filter operates:

  • The tank's dirty water enters with its dirt particles (waste, flakes and many chemical compounds).
  • It passes through the head of the filter, where the pump gives force to the flow.
  • Here are the three parts of the chamber from top to bottom: mechanical filter, biological filter and chemical filter. All the dirt is caught in this chamber, which you will need to clean at least every two weeks.
  • The clean water exists the filter.

What are the different types of filters available?

The time has come to choose the right filter to purify your fish tank. You should know that there are several types of filters out there, classified in two main groups: internal (sponge, box and internal) and external (outdoor and waterfall or backpack). Next we proceed to classify them in a table, with their characteristics.

Type of filter Model Characteristics
Internal Sponge (small fish tanks, or bigger ones with few fish) A foam filtering load working as a mechanical and biological filter. Limited filtering capacity. It needs to be cleaned frequently. Ideal for small fish tanks.
Internal Box or corner (small fish tanks, or bigger ones with few fish) It attaches to the corner of your fish tank via suction cups. It tends to be very affordable. Best for small fish tanks.
Internal Under gravel (small, or larger fish tanks with few fish) It is placed under the substrate of the tank (under the sand or gravel). Weekly gravel cleanings are very important. They are not recommended for freshwater planted tanks.
External (most popular) Canister (medium or large fish tanks) Large flow, due to their storage capacity of filter material. They are easy to manipulate since they are placed outside the aquarium fish tank. These filters are significantly more expensive than internal ones.
External (most popular) Hang on back (HOB) (medium or large fish tanks) For freshwater fish tanks. As the name indicates, it hangs outside the aquarium. The water inlet and outlet tubes are inserted into the water. Full efficiency up to 200 litres. They correctly oxygenate the fish tank. There must always be water for the device to function or it will break.

How do I properly clean my fish tank filter?

The first thing you have to do is to disconnect it from its power source, then remove it from the water — if you opt for an internal filter. You should then clean the dirt and impurities off without using soaps or detergents, as these products are toxic for fish. Repeat with the filter sponge, rinsing it thoroughly with water.

However, you are advised to throw the sponge away if you notice that it is very worn out. If your device has activated carbon, remember that it should be replaced rather than cleaned. You should also remove it when you put medicines in the fish tanks for your pets, as it won't allow the remedy to reach the water.

Shopping Criteria

So many fish tanks are available out there that buying the right one for your home can be a real challenge. However, having the information required will make this task much easier for you. In the following section, we'll discuss some of the key criteria that you should know in order to purchase the aquarium you need for your fish.

  • Capacity and shape
  • Easy-to-clean models
  • Type of fish
  • Additional accessories
  • Customer reviews

Capacity and shape

You should base the size of your fish tank depending on the type of fish you have, as some models can have a maximum capacity of 1,500 litres. However, oxygenation is even more important than size. The shape is also fundamental: rectangular fish tanks are ideal because their shape makes them easy to place in your home.

Another reason why you should opt for a rectangular model is that the surface area in contact with air is larger than other types. This facilitates the exchange of gases — expelling carbon dioxide and absorbing oxygen. The structure of the tank will also influence the amount of light that enters, and this is essential for the plants you have in your aquarium.

A green beautiful planted tropical freshwater aquarium with fishes

Decorating your tank allows you to imitate the natural environment if your fish.
(Source: Bloodua: 25972738/

Easy-to-clean models

This is another key aspect to keep in mind when buying your own fish tank. The goal of having a pet is that you can enjoy its company and provide it with a good life. You can't just sit back thinking that your fish will take care of itself, but it shouldn't be a nightmare for you either. Check how long you'll need to clean both the tank and the filter.

As you might know, cleaning an aquarium is a task that requires resources as well as energy. This is why we encourage you to invest in a fish tank that is easy to clean. You can also opt for a large model that will allow you to place the most suitable filter. That way, you won't have to clean it as often.

Did you know that fish can't close their eyes, but still need to sleep and rest?

Type of fish

This is naturally the most important decision you have to make, as it will determine the type of fish tank you need, as well as all the additional accessories and other decorations you want. In case you didn't know, cold water fish tend to be bigger than tropical fish. The good news is that you can have several species cohabit in the same aquarium.

You can opt for having a communal fish tank. This will cost you more, but it will also be more attractive, in particular if you choose to buy a tropical or Dutch style fish tank. If you're a fishkeeping newbie, you are advised to start off slow to have time to learn as you go. In that regard, we encourage you to pick a cold water fish tank with a couple of fish.


You can easily remove the lime or rush from your fish tank by using a sponge with vinegar or hydrochloric acid.
(Source: Chin Hiran: 37553439/

Additional accessories

You can purchase some aquariums directly as a pack or set — including filters, heaters and other required accessories, or as standalone fish tanks. Your level of skill should help you determine which option is better for you. If you're a novice in the field, for instance, your best choice will probably be to opt for a complete kit that will include everything you need to get started.

On the other hand, if you've already been in the fishkeeping game for some time now, you can easily opt for a fish tank without any additional accessories. You should already have the necessary knowledge to manage all the on your own.

Remember that taking care of fish isn't rocket science. Just like for everything, you simply need to learn the appropriate technique.

Customer reviews

The best thing you can do is to avoid buying a fish tank blindly. That means that you shouldn't let yourself get carried away by attractive prices and pretty images. We encourage you to seek the opinions of other users and even of professionals. Who can know a product better than someone who already has it at home? This may seem obvious, but many people still overlook this useful tool.

One of the best things about online shopping is precisely that you can research, ask and give opinions. You need to use this democratisation of information to your advantage. This is why you should always check the reviews and ratings of past customers whenever you decide to purchase your very own fish tank over the Internet.


Maintaining a fish tank is particularly easy or hard; it simply requires perseverance and dedication. You may have originally thought that having your own fish meant that you didn't have to take care of them. By now, you should know that this isn't true at all: you have to feed them, buy filters, decorations and other products that a fish tank needs to operate properly. You want your fish to live in a clean aquatic space, free of dirt and other debris.

Having a pet at home will bring you great joy, but also a good deal of responsibilities. If you have a fish tank and live alone, it is yours to take care of. On the other hand, if you share your home with other people, we encourage you to divide those responsibilities in order to establish a stronger bond between everyone, including your fish.

This is the end of our guide on fish tanks, and we hope that you found it useful. If that's the case, feel free to leave us a comment in the section below, and share the article on your social media!

(Source of featured image: Bloodua: 25972748/