Archerfish – Toxotes jaculatrix

Among the most fascinating aquarium fish, few attract as much curiosity as the archerfish, Toxotes jaculatrix. Famous for their ability to spit accurate jets of water at insects above the surface, these fish combine unusual behavior with a distinctive appearance. For aquarists willing to recreate their specific conditions, archerfish can become the true centerpiece of a brackish or specialized setup and offer daily opportunities for observation and learning.

Natural environment and behavior of Toxotes jaculatrix

To keep archerfish successfully, it is essential to understand their natural habitat. Toxotes jaculatrix lives in coastal areas of Southeast Asia and Northern Australia, most often in brackish waters where rivers meet the sea. Mangroves, estuaries, flooded forests and tidal creeks are common environments. Water parameters in these zones fluctuate with tides and rainfall, so the species has adapted to a degree of variation that typical freshwater fish do not tolerate as well.

The most famous feature of archerfish is their hunting technique. They patrol the surface, watching branches and leaves above the water. When they spot a small insect or spider, they aim and shoot a jet of water, knocking the prey into the water where it is quickly eaten. This behavior is possible thanks to the shape of their mouth and tongue, which form a kind of barrel used to pressure the water. In nature, the precision of adult archerfish can be astounding: they compensate for refraction and moving targets, hitting insects several times their own body length away.

They are also agile jumpers. If the water jet fails or the prey is too close, archerfish simply leap out of the water to grab it directly. This natural ability is important for aquarium keepers to remember: any tank for Toxotes jaculatrix must have a secure cover. Without a proper lid, these fish may jump out when startled, hunting, or simply exploring the upper surface.

In terms of social behavior, archerfish are not solitary predators. In the wild they are often seen in loose groups. They may hunt together, sometimes even knocking down more insects than they can eat, creating feeding opportunities for other species as well. In the aquarium, they usually tolerate conspecifics, especially when there is enough space, though competition for food and hierarchical behavior can appear. Careful stocking and good feeding practices are key to maintaining harmony.

Visually, Toxotes jaculatrix are attractive fish. They typically have a silvery or whitish body with dark oblique bands or blotches that help them blend among mangrove roots and shimmering surface reflections. Their dorsal fin is set back, near the caudal peduncle, and their body profile is somewhat compressed, ideal for quick turns and accurate surface positioning. The eyes are large and positioned high on the head, perfectly adapted for scanning the area above the waterline.

Planning the aquarium: tank size, layout and equipment

Proper planning is essential before bringing archerfish home. They are not small community fish suitable for modest aquariums. An adult Toxotes jaculatrix can reach 15–20 cm in length. A group of four to six specimens needs a long, spacious tank. For long-term care, a minimum length of 120 cm is recommended, with 150 cm or more being ideal. The larger the group and the more complex the layout, the larger the tank should be.

The height of the aquarium is also important. Because archerfish interact with both the water column and the air above, a higher tank allows for more natural behaviors. However, it is crucial to leave a gap of at least 10–15 cm between the water surface and the lid. This space gives them room to spit and jump without hurting themselves. A tight-fitting, sturdy cover is non-negotiable, both to prevent escapes and to protect lighting and other equipment from their water jets.

When setting up an archerfish aquarium, a horizontal layout works best. Provide open swimming space at the surface where they can patrol, but complement it with vertical structures. Root-like decorations, sturdy branches, and emergent or hanging plants help recreate the feeling of mangroves or riverbanks. These structures also give you natural perches where you can place insects or food items for hunting practice.

Filtration must be robust and reliable. Archerfish are energetic, eat protein-rich foods, and tend to contribute a significant bioload. A high-quality external filter or a well-dimensioned internal filter with strong biological media is recommended. Water movement should be moderate: enough to keep the surface clean and oxygen-rich but not so turbulent that it stresses the fish or makes aiming difficult. Surface agitation helps oxygenation but should not create constant splashing or wave-like turbulence.

Lighting can be medium to strong, especially if you use live plants that tolerate brackish conditions or if you want to highlight the fish’s colors. However, keep in mind that intense light above the water surface can disturb their ability to aim if there are excessive reflections or glaring hotspots. Softly diffused lighting reproduces their natural habitat better. It also enhances the appearance of branches and roots breaking the surface.

MB Store offers a wide selection of aquariums and aquarium equipment suitable for archerfish setups. From larger glass tanks and sturdy covers to external filters, heaters and lighting units, you can find the components needed to build a stable and aesthetically pleasing environment. When planning a tank for Toxotes jaculatrix, it is wise to invest in reliable gear from the start, as these fish reward long-term, carefully designed systems rather than improvised solutions.

Substrate choice is flexible. Sand or fine gravel works well, especially in a pale or natural color that reflects light softly. In a brackish aquarium, coral sand can be used in moderation if you want slightly higher hardness and pH, but you must stay within the species’ preferred parameter range. Decorative rocks, driftwood and inert roots complete the scape and can be combined to create shaded zones where the fish feel secure.

Water parameters and the brackish water debate

One of the most frequently discussed issues in archerfish care is salinity. Toxotes jaculatrix is widely known as a brackish species, yet in nature it may be found from nearly fresh waters up to marine-influenced zones. For aquarium purposes, brackish water is strongly recommended for long-term health, especially for adults.

Brackish water is created by mixing marine salt with freshwater to reach specific gravity values between freshwater and seawater. A typical range for archerfish is 1.005–1.015, measured with a refractometer or hydrometer at 25 °C. Juvenile specimens are sometimes kept in slightly lower salinity, but as they grow, gradually increasing salinity tends to improve vigor and disease resistance. Stability is more important than exact numbers, so choose a point in the recommended range and maintain it consistently.

Temperature should generally be kept between 24 and 28 °C. These fish are tropical and do not tolerate prolonged drops in temperature. A reliable heater with a thermostat is therefore essential. MB Store offers heaters and temperature controllers that help maintain stable conditions even in rooms with fluctuating ambient temperatures. Regular checks with an accurate thermometer are recommended, especially during seasonal changes.

pH in the wild can vary, but in captivity, slightly alkaline conditions around 7.5–8.2 are usually best. Carbonate hardness (KH) and general hardness (GH) should be moderate. Brackish water mixed from marine salt and reasonably hard tap water often naturally falls into the right range, but you should still test regularly, especially after large water changes.

Good water quality is crucial. Ammonia and nitrite must always remain at zero, while nitrate should be kept as low as practicable, preferably below 20–30 mg/l. Because archerfish are messy eaters and enjoy high-protein foods, weekly partial water changes are strongly recommended. When changing water, pre-mix the new water with the correct amount of marine salt and adjust temperature, so the fish do not experience sudden shifts.

Some aquarists attempt to keep archerfish in pure freshwater. While short-term survival is possible, long-term success and full expression of natural behavior are far more likely in brackish conditions. Over time, chronic stress from unsuitable salinity can make the fish more susceptible to disease, reduce lifespan and dull coloration. Creating a true brackish system may seem more complex at first, but with proper planning and equipment, it becomes a straightforward routine.

Feeding: from prepared foods to insect hunting

Feeding Toxotes jaculatrix is one of the most enjoyable aspects of keeping this species. In the wild, archerfish primarily eat insects and small invertebrates that fall or are shot from overhanging vegetation. In the aquarium, we try to simulate this diet while ensuring complete nutrition.

High-quality floating pellets formulated for carnivorous or omnivorous fish are a good base. Pellets should be nutritious, with sufficient protein content and added vitamins. Many archerfish learn quickly to take pellets from the surface, especially if introduced after a period of feeding with more familiar foods such as frozen bloodworms or small shrimp. MB Store carries a variety of specialized feeds and supplements that help maintain strong immunity and growth in predatory species.

Frozen foods such as bloodworms, brine shrimp, mysis and chopped krill provide variety. They should be thawed before feeding and offered at the surface whenever possible. Live foods can be particularly stimulating and closely mimic natural behavior. Crickets, houseflies, small roaches, mealworms (in moderation) and other safe insects encourage natural hunting. Ensure that any insects used are free from pesticides and other contaminants.

One of the unique joys of keeping archerfish is training them to shoot. Carefully place an insect or a small piece of food on a leaf or piece of driftwood above the water surface. Step back and wait. Often, after a period of observation, one fish will aim and fire. Once they succeed a few times, they tend to repeat the behavior more confidently. It is not only entertaining but also meaningful enrichment, engaging their instinctive hunting patterns.

Beware of overfeeding. Enthusiastic owners may be tempted to offer too many insects and high-fat foods. Obesity and fatty liver can be real issues in predatory species kept in captivity. Feed adults once or twice a day, giving only as much as they can consume within a few minutes. Occasional fasting days can help maintain good health. Juveniles, however, may require more frequent but smaller meals to support growth.

Supplementation with vitamins and, where appropriate, carotenoid-rich foods can help maintain intense coloration and robust immunity. This becomes particularly important if you rely mainly on frozen foods, which can lose some nutritional value over time. Consulting feeding guidelines and product descriptions from trusted sources, such as those available at MB Store, can help you choose the best feeding strategy for your particular group of archerfish.

Tankmates and community options

Choosing suitable tankmates for archerfish requires careful thought. Toxotes jaculatrix is a predator specialized for surface hunting. Any small fish that swim near the surface may eventually be seen as food. Therefore, tankmates must be large enough not to be considered prey and must tolerate the same brackish conditions.

Good companions are generally robust brackish species of similar size. Larger monos, scats and some pufferfish that thrive in brackish water can be considered, provided the aquarium is sufficiently large and territorial or aggressive behavior is managed. Many gobies adapted to brackish environments make interesting bottom dwellers, adding life to the lower zones of the aquarium without directly competing for the same niche.

Remember that archerfish are quite active and may startle slower or timid fish. They also dominate the upper water layers. Avoid keeping them with very shy species that require calm surroundings, as these tankmates may spend most of their time hiding. Midwater schooling fish that can handle brackish water and reach a reasonable size can work well, as they occupy a different vertical space and add movement without threatening the archerfish themselves.

Invertebrates are more problematic. Many common aquarium shrimps, snails or crabs are either not suited to brackish conditions or are too tempting as prey. Large, heavily armored species might survive but can introduce other challenges, such as aggression or predation on fish. In most cases, a fish-only brackish setup or one with minimal invertebrates is the best option for Toxotes jaculatrix.

Keeping archerfish with conspecifics is often desirable. A group mimics their natural social environment and can reduce individual timidity. However, hierarchy may develop, and weaker fish may be outcompeted for food in cramped conditions. Providing ample space, visual barriers created by decorations, and distributing food across the surface during feeding sessions help minimize tension.

Aquascaping and plants in an archerfish aquarium

Aquascaping a tank for archerfish is an opportunity to create a striking and functional display. Rather than a densely planted freshwater layout, think in terms of a mangrove or estuarine scene. Use branching driftwood to suggest roots penetrating the water, with some pieces emerging above the surface. These emergent branches serve multiple purposes: they provide resting spots for insects used as food, break up the line of sight and offer visual interest above and below the waterline.

Rock structures should be stable and carefully placed, as archerfish are powerful swimmers and can easily knock over poorly balanced decor. Arrange rocks and wood to create caves and sheltered zones, not so much for the archerfish themselves but for any tankmates and for aesthetic depth. A clean foreground of sand with scattered roots and leaves often looks very natural and emphasizes the open surface used by Toxotes jaculatrix.

Plant selection in brackish water is more limited, but some species tolerate low to moderate salinity. Java fern and some types of Anubias, mounted on driftwood or rocks, can survive in mild brackish setups if acclimated gradually. Floating plants may struggle at higher salinities, yet they can be used in lower-end brackish systems to diffuse light and create a more complex surface. Always research the salinity tolerance of the plants you choose.

An alternative to underwater plants is to focus on emergent and riparian vegetation. Pots with hardy terrestrial or semi-aquatic plants can be integrated around or above the tank, with roots trailing into the water if appropriate. This approach creates the impression of a flooded shoreline. Overhanging leaves from such plants make perfect targets for archerfish hunting practice, allowing you to place insects in natural-looking positions.

Because the upper 10–15 cm of the tank should remain water-free under the lid, you can use this volume to emphasize vertical elements. Branch tips, artificial mangrove roots or decorative structures can occupy this zone. Combined with appropriate lighting, it creates a layered appearance reminiscent of natural habitats and encourages the fish to explore and interact with their environment.

Health, maintenance and long-term care

Keeping Toxotes jaculatrix healthy over many years requires consistent maintenance and attention to early signs of problems. Stress is a major factor in disease for all aquarium fish, and archerfish are no exception. Causes of stress can include inappropriate salinity, sudden changes in temperature or pH, poor water quality, aggression from tankmates or constant disturbance near the aquarium.

Regular water testing is essential. Monitor ammonia, nitrite, nitrate, pH, hardness and salinity. Establish a maintenance routine with weekly or biweekly partial water changes of 20–30%. During these changes, carefully vacuum debris from the substrate, especially food remnants that can decompose and pollute the water. Clean filter media in aquarium water, not under the tap, to preserve beneficial bacteria.

Observe the fish daily. Early warning signs of trouble include reduced appetite, lethargy, clamped fins, abnormal swimming near the bottom, frequent rubbing against objects or breathing difficulties at the surface. External symptoms like white spots, cloudy eyes or frayed fins require prompt diagnosis and treatment. Since archerfish are kept in brackish water, some common parasites and pathogens may be less prevalent, but they are not immune to disease.

Quarantine is strongly recommended for new arrivals. A separate tank with appropriate salinity and temperature allows you to monitor newcomers for a few weeks before introducing them to the main display. This practice protects your established group and reduces the risk of outbreaks. MB Store can provide smaller aquariums, heaters and simple filtration systems ideal for setting up quarantine or hospital tanks.

Archerfish are intelligent and responsive to their environment. Boredom is rarely discussed in aquaristics, but with such active predators, environmental enrichment makes a difference. Varying the feeding method, rearranging small parts of the décor and occasionally adding new structures can stimulate exploration. Just avoid drastic changes that would cause stress; instead, think in terms of gradual evolution of the scape.

With proper care, Toxotes jaculatrix can live for many years in captivity. Reports of lifespans of 8–10 years are not unusual when kept under stable conditions. This long-term commitment underscores the importance of investing in good equipment from the start. Reliable filters, heaters, lighting and a spacious tank from suppliers like MB Store ensure that your archerfish have the best chance to thrive and display their remarkable natural behaviors.

Is the archerfish right for your aquarium?

Deciding whether to keep archerfish is ultimately a question of matching your expectations, available space and willingness to maintain a specialized setup. Toxotes jaculatrix is not the easiest beginner fish. Their need for brackish water, large tanks, secure lids and specific diet means they are better suited for aquarists with some prior experience or strong motivation to learn.

However, for those prepared to meet these requirements, archerfish are among the most rewarding species in the hobby. Few fish offer such direct interaction with the environment above the waterline. Watching them stalk a fly perched on a branch, carefully adjust their position, and then shoot with astonishing accuracy is an experience that transforms the aquarium from a decorative object into a dynamic and educational display.

They also serve as excellent ambassadors for the diversity of aquatic ecosystems beyond classic freshwater or reef aquariums. A well-designed brackish tank reflects the transitional zones between river and sea, highlighting the complexity of mangrove systems and tidal estuaries. For aquarists fascinated by biotopes, Toxotes jaculatrix offers an opportunity to create a unique slice of nature in the living room or office.

If you are considering this species, start with careful planning. Determine the space where the aquarium will stand, the maximum dimensions you can accommodate, and your budget for equipment. Browse the range of aquariums, filters, heaters and lighting at MB Store, and choose components that will provide not only for the current fish but also for their adult size and future companions. Proper planning reduces the need for major upgrades later and helps ensure a stable, enjoyable system from the beginning.

In summary, the archerfish, Toxotes jaculatrix, is an extraordinary aquarium inhabitant for dedicated keepers. Its unique hunting behavior, striking appearance and interactive nature elevate the entire fishkeeping experience. With appropriate tank size, carefully maintained brackish water, thoughtful aquascaping and a varied, high-quality diet, archerfish can become the star of a truly unforgettable aquarium.

FAQ – Archerfish (Toxotes jaculatrix) in aquariums

Can archerfish live in freshwater only?
Archerfish may survive in freshwater for some time, especially when young, but long-term health is best in brackish water. Brackish conditions support stronger immunity, better coloration and more natural behavior. For adult Toxotes jaculatrix, maintaining stable, moderate salinity is strongly recommended for optimal welfare.

What tank size do I need for archerfish?
For a small group of archerfish, a tank at least 120 cm long is advisable, with 150 cm or more preferred for adult specimens. These active surface swimmers need horizontal space and depth for jumping room. A generous footprint also helps reduce aggression, allows for complex aquascaping and keeps water quality more stable between maintenance.

Do archerfish get along with other fish?
Archerfish can coexist with suitable brackish tankmates of similar size or larger. Avoid small species that fit into their mouths, as they may be eaten. Robust monos, scats and some gobies can work if the aquarium is large enough. Ensure all inhabitants tolerate the same salinity and monitor interactions, especially during feeding, to prevent bullying.

How do I train archerfish to spit at food?
Start by placing small insects or food pieces on branches just above the surface. At first, they may grab food by jumping. Over time, one fish usually attempts a water jet. After the first success, others learn quickly. Keep sessions short, use safe insects and avoid overfeeding. This training enriches their lives and encourages natural hunting.

Is keeping archerfish suitable for beginners?
Archerfish are better for aquarists with some experience. They require a large tank, brackish water, secure lids and a varied, protein-rich diet. Beginners willing to research, invest in proper equipment from MB Store and follow stable maintenance routines can succeed, but those seeking a simple community aquarium may wish to start with easier freshwater species first.