Guppy – Poecilia reticulata

Among all freshwater aquarium fish, few species are as iconic and universally loved as the guppy, Poecilia reticulata. Hardy, colourful, active and endlessly interesting to watch, guppies are a perfect choice both for beginners and for advanced aquarists planning complex community tanks. In this article we explore their origins, behaviour, care requirements and breeding, as well as practical equipment recommendations. At MB Store you will find complete aquariums, filtration systems and other aquarium accessories tailored to guppy keeping.

Natural origin and characteristics of Poecilia reticulata

The guppy, scientifically known as Poecilia reticulata, comes from the warm waters of northern South America and several Caribbean islands. There it inhabits slow-flowing streams, small rivers and temporary pools rich in vegetation. These environments are characterised by fluctuating water parameters, which partly explains the legendary hardiness of guppies in the aquarium hobby. They cope well in conditions that would be too unstable for many more delicate species.

In the wild, guppies are relatively inconspicuous; the most spectacular forms have been created through decades of breeding. Males are smaller but much more colourful, with long, flowing tails and dorsal fins. Females are larger, with a fuller body and less intense colours, but they can still be very attractive, especially in well-selected lines. An important feature of guppies is their status as livebearers: instead of laying eggs, females give birth to fully formed, free-swimming fry. This makes their reproduction in the aquarium exceptionally easy and attractive for aquarists.

The enormous variety of colour morphs and tail shapes is one of the reasons why guppies are so popular. Among breeders you can find guppies with tails in the shape of fans, triangles, lyres, spears or double swords, and colours ranging from intense reds and blues to metallic greens, blacks and multi-coloured mosaics. Selective breeding has also led to lines focused on improved immunity, larger size or more intense pigmentation, which significantly increases their value for both hobbyists and professional breeders.

In spite of their delicate look, guppies are quite robust. They tolerate a wide spectrum of water parameters and temperature ranges. This resilience, however, does not mean that they can be kept in any conditions without consequences. Chronic stress, poor water quality or overstocking will eventually lead to diseases and shortened lifespans. Understanding their natural habitat helps set standards for good care: clean water, appropriate group structure, access to shelter among plants and a balanced diet.

Choosing the right aquarium and equipment for guppies

When planning a tank for guppies, it is important to combine aesthetic expectations with the real biological needs of the fish. Although guppies are small, they are very active swimmers which use the entire water column. For a small group of guppies, an aquarium of at least 40–54 litres is recommended, and for larger communities or mixed setups with other species, 60–100 litres or more will provide stable conditions and more room for natural behaviour. At MB Store you can find complete aquarium sets and individual tanks in various capacities, making it easy to adapt the size to your own plans and available space.

The core of every guppy tank is efficient filtration. Guppies eat eagerly and reproduce quickly, which increases the organic load in the water. A well-chosen filter supports biological, mechanical and, if necessary, chemical filtration, maintaining low levels of ammonia and nitrites, and stabilising nitrates. For guppies, internal filters with a sponge and ceramic media or external canister filters in larger tanks work very well. In MB Store’s offer you will find filters adjusted to different volumes, allowing you to select a model with proper flow without generating excessive current that could tire the fish.

Another key element is heating. Guppies feel best at 23–26°C, although they can survive a wider range. Stable temperature reduces stress and the risk of disease. An adjustable heater with thermostat should be adapted to the size of the tank, typically 1 W per litre of water. Modern heaters available at MB Store include built-in thermostats and often additional protection, such as automatic shut-off when removed from water, which increases safety both for the fish and for the aquarist.

Lighting in a guppy aquarium serves a double purpose. First, it allows us to fully admire their colours, which are significantly enhanced under suitable light. Second, it supports the growth of aquatic plants, which provide shelter and improve water quality. Energy-efficient LED lighting is now standard in most sets. Many models offered by MB Store allow you to adjust intensity and sometimes colour temperature, so you can emphasise reds or blues in the fish and at the same time ensure good conditions for plants.

In addition to the basic equipment, it is worth equipping the tank with a tight cover or lid, as guppies, especially frightened ones, can jump above the water surface. A cover also reduces evaporation and helps maintain a stable temperature. Accessories such as thermometers, nets, siphons for cleaning the substrate and test kits for monitoring water parameters are also extremely helpful. In MB Store you can assemble a complete set of aquarium equipment needed to start and maintain a healthy guppy tank, from basic elements to specialised accessories for advanced aquarists.

Water parameters and aquascaping for guppies

Success in guppy keeping largely depends on providing appropriate and stable water conditions. Guppies prefer slightly alkaline water with moderate hardness. A pH in the range of 7.0–8.0 and general hardness (GH) from 8 to 15°d are usually well tolerated. However, they are quite adaptable and can also live in slightly softer or more acidic water, as long as changes are not sudden. The key factor is stability; rapid swings in pH or hardness are more harmful than slightly suboptimal values.

Regular testing of water parameters allows early detection of potential problems. Ammonia and nitrite levels should always be kept at zero, while nitrate concentration ideally remains below 30–40 mg/l. To maintain these conditions, weekly water changes of 20–30% of the tank volume are recommended, although heavily stocked aquariums with many guppies or intensive feeding may require more frequent or larger changes. At MB Store you can find liquid tests, strips and accessories facilitating water changes, such as siphons and water conditioners neutralising chlorine and chloramines.

When designing aquascaping for a guppy tank, it is worth finding a balance between open swimming areas and dense plant zones. Guppies like to stay near the surface and in the mid-water regions, so it is important that plants do not completely dominate these spaces. A composition with a clear foreground and middle section for swimming and denser plant groups in the background works very well. Plants such as Vallisneria, Hygrophila, Limnophila or various mosses provide cover for fry and create a natural environment that reduces stress.

Floating plants, for example Ceratopteris, Salvinia or Pistia, are particularly beneficial. They diffuse the light, making guppies feel safer and less shy, and at the same time act as an additional biological filter, absorbing nitrates directly from the water. However, it is worth ensuring that floating plants do not cover the entire surface, as guppies need easy access to oxygen-rich water and space to feed. A slight movement of water from the filter outlet or air stone will prevent stagnation and support gas exchange.

The bottom substrate in a guppy aquarium can be fine gravel or sand, depending on aesthetic preferences and chosen plants. Darker substrate nicely emphasises the colours of fish and reduces light reflection that might stress them. Decorations such as roots, stones, caves or ceramic structures provide hiding places for shy individuals and resting points for females trying to avoid persistent males. All decorations should be safe for aquarium use and not change water chemistry unfavourably. In MB Store you will find carefully selected substrates and aquascaping materials that allow you to create both naturalistic and more modern, minimalist layouts.

Social behaviour and suitable tank mates

Guppies are social fish that feel best in groups. A basic community should consist of at least several individuals. It is recommended to maintain an appropriate ratio of males to females; usually one male per two or three females works well. This helps distribute the attention of males and reduces stress for females, which might otherwise be constantly pursued for mating. In larger tanks, you can create more complex structures, with several groups of guppies of different colour morphs, yet still keeping an eye on the overall balance.

Despite their lively temperament, guppies are generally peaceful. They rarely show aggressive behaviour, although males may compete for females or food. Such skirmishes are usually harmless and limited to short chases or fin displays. Problems occur mainly in overcrowded aquariums or where the spatial arrangement does not allow fish to avoid one another. A well-planned layout with plants and decorations significantly reduces potential conflicts and allows each fish to find its own niche.

Choosing tank mates for guppies requires taking into account both behaviour and water parameter preferences. Peaceful species such as small tetras, Corydoras catfish, Otocinclus algae eaters or some smaller rasboras usually make good companions. On the other hand, aggressive or fin-nipping species, like many barbs, larger cichlids or some gouramis, can attack guppies, especially their long tails. Therefore, mixing guppies with such fish is not advisable for the long-term health of the community.

It is also worth remembering that guppies are small and may become prey for larger predators. Even if a bigger fish fits in the same parameter range, the size difference can lead to problems. When planning stocking, always consider the adult size of all species. In MB Store you will find descriptions and recommendations for many fish species, which helps in choosing compatible inhabitants for a guppy tank and avoiding risky combinations that could end in stress or losses.

Occasionally, guppies themselves may nip fins of other fish, especially if they are kept in cramped conditions or are bored due to a lack of environmental enrichment. To minimise this risk, provide them with varied surroundings, proper group structure and sufficient food. Observing daily interactions allows early detection of emerging conflicts. If a certain combination of species does not work, it is better to reorganise the stock than to wait until injuries or disease appear.

Feeding guppies: diet and nutrition

Guppies are omnivores with a strong inclination towards small invertebrates and plant material. In the aquarium, they will accept almost any food, but quality and variety are key to maintaining their health and intense colouration. A base diet should consist of high-quality flake or micro-granule food formulated for tropical fish or, preferably, specifically for livebearers. Such foods typically contain a balanced blend of proteins, fats, carbohydrates and vitamins, supporting growth, fertility and immune function.

To enhance colour intensity and overall condition, it is advisable to supplement the diet with live or frozen foods. Daphnia, Artemia, cyclops, grindal worms or fine bloodworms (used sparingly) are excellent sources of protein and natural pigments. Regular, but not excessive, feeding with such items strengthens fish, stimulates natural hunting behaviour and supports reproduction. However, it is important to avoid overfeeding. Uneaten food quickly decomposes and degrades water quality, leading to elevated levels of nitrogen compounds.

Plant-based supplements also play an important role in the diet of guppies. Foods with added spirulina, finely chopped blanched vegetables such as spinach or zucchini, and special vegetable wafers (eaten in small pieces) provide fibre and micronutrients. They support the digestive system and reduce the risk of constipation, which sometimes occurs in fish fed exclusively on dry, high-protein food. Guppies also like to nibble on soft algae and biofilm forming on decorations and plants, which is a natural behaviour helping them complement their diet.

Feeding frequency should be adjusted to the age and number of fish. Adult guppies do well on two small meals a day, while fry and young fish may require three to four smaller portions to support rapid growth. Each feeding should last only a few minutes; food that remains after that time usually ends up on the bottom and starts to rot. Automatic feeders, available at MB Store, can be helpful for aquarists who are often away from home, ensuring regular feeding while avoiding sudden large doses of food.

In addition to diversified nutrition, access to clean, well-filtered water contributes to efficient digestion and nutrient absorption. Occasional fasting days, when fish receive no food for 24 hours, can help clear their digestive tract and prevent obesity. Observing the body shape and activity of guppies is a good indicator of whether the diet is appropriate. Well-fed fish are energetic, have full but not swollen bellies, and display strong colours and smooth fins without fraying or opacity.

Breeding guppies in the home aquarium

Reproduction is one of the most fascinating aspects of keeping guppies. As livebearing fish, they do not lay eggs but give birth to fully developed fry. This makes breeding relatively simple, yet it requires certain preparations if you want to maximise survival and maintain desired traits. Sexual maturity is reached very quickly, often at two to three months of age, depending on conditions. Males continuously court females, displaying their fins and performing zigzag dances to win their attention.

Fertilisation occurs internally. Females can store sperm, which means a single mating can result in several subsequent litters over a period of weeks or even months. The gestation period usually lasts 25–30 days, depending on temperature and diet. As birth approaches, the female’s abdomen becomes more rounded, and the characteristic dark gravid spot near the anal fin becomes more visible. Behavioural changes, such as seeking shelter and reduced appetite, also signal imminent birth.

In community tanks, adult guppies often eat some of their own fry, especially if there are no dense plants providing cover. To increase survival, aquarists sometimes move pregnant females to separate breeding tanks or use special breeding boxes. However, these methods can also cause stress if used improperly. A more natural approach is to arrange thick plant thickets, especially with fine-leaved species and mosses, where newborn fry can hide immediately after birth. With sufficient cover, a part of the brood usually survives even in a community setting.

Fry care is relatively simple. Newborn guppies are large enough to accept crushed flake food, micro-pellets or specialised fry feeds. For optimal growth, you can also offer them freshly hatched Artemia nauplii, which provide valuable proteins and stimulate vigorous development. Frequent, small meals combined with excellent water quality result in fast growth and reduced susceptibility to disease. Regular partial water changes are crucial, as fry are more sensitive to elevated levels of pollutants than adult fish.

Selective breeding allows you to develop and stabilise specific colour and fin patterns. This requires separating lines, carefully selecting breeding stock and avoiding random crossing of different morphs, which can lead to loss of desirable traits. Advanced breeders often maintain several tanks for different lines, keeping detailed records of parents and offspring. At MB Store you can equip such a breeding setup with multiple small aquariums, sponge filters and heaters, creating an efficient and safe system for guppy genetics projects.

Health, diseases and preventive care

Although guppies are hardy, they can fall ill, especially in poor conditions. Many health issues are directly related to stress, improper water parameters or inadequate diet. The most common problems include fin rot, white spots (ich), fungal infections, bacterial diseases and various internal parasites. Observation of daily behaviour allows early recognition of alarming symptoms: clamped fins, rubbing against decorations, rapid breathing, loss of appetite or unusual body posture usually indicate that something is wrong.

Prevention is always better than treatment. Maintaining stable, appropriate water parameters, regular water changes, non-overcrowded tanks and a balanced diet significantly reduce the risk of disease. When introducing new fish, it is advisable to apply quarantine, keeping them in a separate tank for at least two weeks. This allows observation and potential treatment without exposing the main population. Quarantine tanks can be small but should have filtration, heating and hiding places. MB Store supplies practical solutions for such setups, including compact filters and heaters suitable for temporary use.

In case of disease, proper diagnosis is crucial. Different illnesses require distinct treatments, so indiscriminate use of random medications can do more harm than good. A detailed description of symptoms, supported by photos and water test results, helps identify the cause. Sometimes slight corrections in water quality and improved feeding are enough to restore health, while in other cases targeted medications are necessary. It is important to follow the manufacturer’s instructions, remove activated carbon from the filter during treatment and monitor fish closely during the process.

Chronic problems such as recurring fin damage or frequent infections often indicate systemic issues in aquarium management. Overcrowding, insufficient filtration or neglected cleaning cannot be compensated by medications alone. In such situations, a comprehensive review of the entire setup is needed: from stocking levels and feeding patterns to maintenance routines and equipment efficiency. Using reliable gear from MB Store and following recommended practices creates an environment where guppies can live long, healthy lives, often exceeding two or even three years, which is significant for such small fish.

Guppies as a gateway to advanced aquaristics

For many aquarists, guppies are the first fish species they ever keep, but they can also become a bridge to more advanced aspects of the hobby. Their ease of breeding encourages experiments with genetics, colour morphs and selective line development. Observing inherited traits from one generation to the next not only brings satisfaction but also introduces basic principles of heredity, making guppies a fascinating model for learning and exploration. Dedicated breeders achieve spectacular results, creating unique lines that become the pride of their collections.

Guppies are also well suited for participation in aquascaped tanks, where the aesthetic arrangement of plants, stones and wood plays a central role. Their lively behaviour and bright colours complement both classic, lushly planted layouts and more minimalist compositions. By adjusting lighting, choosing contrasting plants and substrates, and introducing interesting structural elements, you can create an aquarium that is both visually impressive and comfortable for the fish. MB Store offers a wide selection of equipment and decorative materials, enabling transformation of any guppy tank into a remarkable living picture.

Another advanced area associated with guppy keeping is the design of multi-tank systems. Enthusiasts of breeding and selection often operate several or even dozens of aquariums connected in a common system or run separately. Efficient management of such setups requires thoughtful filtration solutions, heating and lighting planning, as well as organisational skills. The modular nature of many products available at MB Store makes it easier to expand systems gradually, adapting them to growing ambitions and experience.

Guppies, with their combination of beauty, hardiness and interesting behaviour, perfectly fit into various stages of aquaristic development. They are forgiving of beginner mistakes yet provide enough complexity to stay engaging even after many years in the hobby. Whether you are planning your first small community tank or a sophisticated breeding station, MB Store can supply the essential equipment, from reliable filters and heaters to decorative elements and professional foods. With the right approach, guppies will reward you with vivid colours, dynamic activity and countless hours of observation that transform an ordinary aquarium into a dynamic, thriving ecosystem.

FAQ about guppies – Poecilia reticulata

How many guppies can I keep in my aquarium?
In a beginner setup, it is wise to plan roughly one guppy for every 4–5 litres of water, but only in a well-filtered, mature tank. For instance, a 60-litre aquarium can host around a dozen adults. Remember that guppies reproduce rapidly, so the population may increase quickly. Consider future fry, filter capacity and regular maintenance when deciding on stocking levels.

What is the ideal water temperature for guppies?
Guppies feel best at 23–26°C, which supports strong immunity, fertility and vivid colouration. Short-term fluctuations outside this range are tolerated, but prolonged cold slows metabolism and weakens resistance to disease, while overly high temperatures reduce oxygen in the water. Use a reliable heater with thermostat and regularly check temperature with a thermometer for stability.

Can guppies live with other fish species?
Yes, guppies are generally peaceful and suitable for community tanks. Choose companions that are similar in size, calm and not prone to fin-nipping. Small tetras, Corydoras and some rasboras work well. Avoid large or aggressive fish and species known for biting fins. Always check compatibility of water parameters and monitor early interactions to ensure a safe, stress-free environment.

How do I recognise a pregnant guppy female?
A pregnant guppy has a noticeably enlarged abdomen and a dark gravid spot near the anal fin that becomes more visible over time. Shortly before birth she may seek shelter, become more withdrawn and show reduced appetite. Gestation usually lasts about four weeks. Providing dense plants or a separate breeding tank increases fry survival and reduces stress for the female.

What should I feed guppy fry?
Newborn guppies can immediately eat very fine foods such as powdered flakes, specialised fry granules or freshly hatched Artemia. Offer small portions several times a day so food is consumed quickly and does not pollute the water. Clean, stable water and regular partial changes are crucial. With good nutrition and care, fry grow rapidly and can resemble adults in just a few months.