5 Best Freshwater Fish for Beginners

Getting started with a freshwater aquarium is an exciting experience, but choosing the first fish can quickly become complicated. Aquarium size, water parameters, the behaviour of different species and their specific requirements all need to be considered, as not every fish is suitable for a beginner aquarium.

For the best possible start, it is preferable to choose relatively hardy species with requirements that are manageable for beginner aquarists. However, this does not mean that they can live in just any conditions: even fish considered easy to care for need a properly cycled aquarium, suitable water conditions and regular maintenance.

Guppies, Platies, Zebra Danios, Corydoras aeneus and Bettas: here are 5 freshwater fish suitable for beginners and the key information to consider before adding them to an aquarium.

How to choose freshwater fish for a first aquarium

Choosing a fish should not be based on appearance alone. Before introducing any fish, it is essential to consider its adult size, behaviour, specific requirements, compatibility with other inhabitants and the aquarium’s water parameters.

The available aquarium volume is also an important factor. A small fish is not necessarily suitable for a small aquarium: some species need to live in groups or require sufficient swimming space.

Water parameters must also be taken into account. Temperature, pH and hardness requirements can vary from one species to another. If several fish species are to be kept together, their requirements must therefore be compatible.

Finally, even when choosing species considered hardy, it is essential to wait until the nitrogen cycle is properly established before introducing the first fish.

1. Guppy

Colourful, active and easy to observe, the Guppy is one of the best-known freshwater aquarium fish. Males are particularly appreciated for their vibrant colours and large fins.

Native to tropical regions of the Americas, Guppies generally prefer harder, more alkaline water in an aquarium.

The Guppy is a social fish that benefits from the presence of others of its kind. However, its ability to reproduce very easily must be taken into account. Guppies are livebearers: females give birth to fully formed fry, and numbers can increase rapidly when males and females are kept together.

For beginner aquarists, it is therefore important to anticipate this reproduction to prevent the population from becoming too large.

With its lively behaviour, wide variety of colours and relatively straightforward care requirements when its needs are met, the Guppy remains an excellent fish for discovering freshwater fishkeeping.

2. Platy

The Platy is another particularly popular freshwater aquarium fish. Peaceful, colourful and active, it has many qualities that make it suitable for a first experience with fishkeeping.

Native to Central America, Xiphophorus maculatus prefers relatively hard, alkaline water. Numerous varieties are also available in different colours and patterns.

The Platy is a social fish that benefits from the presence of others of its kind. Like the Guppy, it is a livebearer and can reproduce easily in an aquarium. Population numbers therefore need to be monitored when males and females are kept together.

Its generally peaceful temperament and relatively straightforward care requirements make it a particularly interesting species for beginner aquarists.

3. Zebra Danio (Danio rerio)

Active and easily recognised by its horizontal stripes, the Zebra Danio (Danio rerio) is an interesting species for beginners setting up a freshwater aquarium.

Native to South Asia, this small fish is known for its particularly active behaviour.

The Zebra Danio is a shoaling species. It should therefore not be kept alone, but with several others of its own kind. Observing these fish swimming together allows their more natural behaviour to be seen.

Its small size does not mean that it should be kept in a confined space. The Zebra Danio is an active swimmer and requires an aquarium with sufficient length to move around freely.

It tolerates a relatively broad temperature range for a fish commonly kept in aquariums. Nevertheless, any tank mates should have requirements compatible with its own.

Hardy and highly active, the Zebra Danio is therefore an interesting choice for a first aquarium, provided that its need to live in a group and have sufficient swimming space is respected.

4. Corydoras aeneus

Corydoras aeneus is a bottom-dwelling fish native to South America. With its peaceful behaviour and characteristic way of exploring the substrate, it brings a different dynamic to a community aquarium.

This social species should be kept with several others of its own kind. In a group, these fish explore the bottom of the aquarium and regularly interact with one another.

The choice of substrate deserves particular attention. Corydoras use their barbels to search for food along the bottom, so a fine, non-abrasive substrate is preferable.

A common misconception is that Corydoras are simply “cleaner fish”. Although they may pick up some food from the bottom of the aquarium, they do not replace regular aquarium maintenance and must receive a diet suited to their own nutritional requirements.

Aquarium size should be chosen with both their adult size and their need to be kept in a group in mind.

Peaceful and interesting to observe, Corydoras aeneus is a good choice for a beginner aquarist looking to keep fish that spend most of their time near the bottom of the aquarium.

5. Betta (Betta splendens)

With its intense colours and spectacular fins, the Betta splendens, also known as the Siamese fighting fish, is one of the most recognisable freshwater fish.

Native to Southeast Asia, the Betta has a remarkable characteristic: in addition to its gills, it possesses a respiratory organ known as the labyrinth organ, which allows it to breathe atmospheric air at the surface. It is therefore perfectly normal to see a Betta regularly coming to the surface to breathe.

However, this ability does not mean that it can be kept in a small container without appropriate equipment. Bettas also require a properly set up, heated and regularly maintained aquarium.

They prefer calm, planted environments. Excessive water flow can be uncomfortable, particularly for varieties with long fins.

Males are particularly territorial, and two males should not be kept together. Compatibility with other fish must also be carefully considered according to aquarium size, layout and the temperament of the species involved.

The Betta can therefore be a very good fish for beginners, particularly for an aquarium focused primarily on a single species rather than immediately creating a large community of fish.

Can these 5 freshwater fish be kept together?

This selection should not necessarily be considered a stocking plan to reproduce exactly in the same aquarium. In an aquarium of at least 450 litres, with a neutral pH of around 7 and conditions suited to the requirements of each species, keeping them together may be considered. In contrast, in a 60-litre aquarium, keeping Guppies and a Betta together, for example, is best avoided.

These five species can all be good freshwater fish for beginners, but their requirements and behaviours are not identical.

Guppies and Platies generally prefer harder, more alkaline water. Zebra Danios require sufficient space to swim as a group. Corydoras aeneus also needs to live with others of its own kind, while Bettas display territorial behaviour that requires greater care when selecting tank mates.

It is therefore preferable to build an aquarium community around compatible species rather than choosing several fish simply because they are considered easy to care for.

What mistakes should be avoided with the first fish?

One of the most common mistakes is introducing fish too soon after setting up an aquarium. The biological cycle must be properly established before fish are added, particularly to avoid dangerous exposure to nitrites.

Overstocking should also be avoided. Adding several species without considering their adult size, behaviour or need to live in groups can quickly result in a population that is unsuitable for the available aquarium volume.

Another common mistake is choosing fish based solely on their appearance or size. Even small species may require considerable space because of their activity levels or social behaviour.

Finally, a fish described as “easy” is still an animal with specific requirements. Water quality, an appropriate diet, regular aquarium maintenance and compatibility between inhabitants remain essential.

What is the best freshwater fish for beginners?

There is no single best freshwater fish for beginners. The right choice depends primarily on the type of aquarium, its volume and the characteristics of the available water.

Guppies and Platies are popular for their colours and active behaviour, but their reproduction must be anticipated. Zebra Danios are particularly well suited to aquariums that provide sufficient swimming space. Corydoras aeneus offers the opportunity to observe different group behaviour near the bottom, while the Betta is an interesting option for an aquarium focused more closely on a single species.

Rather than choosing a fish simply because it is considered hardy, the key is to create a coherent aquarium around fish whose requirements can be properly met.

A properly cycled aquarium, a population suited to the available volume and appropriate water parameters provide the best foundations for getting started with a freshwater aquarium.