Top 5 essentials you need for zebrafish breeding tanks

How to make heavy-duty shelving for fish tanks stronger
How to make heavy-duty shelving for fish tanks stronger

Zebrafish (Danio rerio) have become a cornerstone of scientific research due to their rapid life cycle and genetic similarities to humans. As a study model, these attributes make them particularly valuable in genomics and pharmaceutical research. The key to this type of research is successful zebrafish breeding and animal well-being. Like most things, having the right tools and materials does matter. Based on our 15 years of experience  with aquatic researc centres, as a fish tank rack system specialist, here is the best equipment needed for zebrafish breeding tanks.

1. Robust & modular fish tank rack systems for zebrafish projects

A well-designed and durable fish tank rack system is the backbone of any zebrafish research facility. These systems need to accommodate the unique needs of zebrafish, ensuring that they have an optimal habitat for breeding and experimentation.

Materials and tank types for zebrafish

Common materials for zebrafish tanks include glass, food-grade plastics, PVC, and plexiglass. We recommend using tanks made of polycarbonate or polysulfone since they are autoclavable, making them easy to clean and reuse. Each material has advantages in terms of durability, ease of cleaning or visibility. Besides, choosing the appropriate water volume (from 1 to 8 litres) is crucial. Proper tank design also encourages gas exchange by optimising the surface-to-depth ratio. Finally, it’s important to remember that before filling the tanks with water, they must be cleaned and rinsed thoroughly to eliminate dust and potential contaminants.

Key features of zebrafish tanks used for breeding

Zebrafish tanks must cater to specific breeding needs. A key feature is the ability to tilt the tanks by creating a shallower area with a depth gradient. It favours a breeding behaviour in zebrafish. Using a mesh, a grid or marbles at the bottom of the tank protects fertilised eggs from potential cannibalism by adult fish. Additionally, consider using automated feeding methods. It can be a game-changer. Smart feeding solutions ensure that the right fish receive the correct type and quantity of food without errors, optimising fish health and growth.

Robust fish tank rack systems

The value of the specimens of zebrafish housed in aquatic research centres can be tremendous. A failure in a rack system can result in significant losses. At Luxaqua, while we do not sell zebrafish tanks specifically, we specialise in custom-made fish tank rack systems. They are used mainly by research institutes studying other popular aquatic species models such as clownfish, cuttlefish or xenopus. As a result, we know the best practices for maximising space while ensuring security and ease of maintenance. Our priority is to offer favourable conditions for the well-being of the zebrafish.

Fish tank rack systems, either for breeding or experimentation, must be multifunctional and modular, offering flexibility for various research projects. Since zebrafish are sensitive to vibrations, stable shelving made from durable materials such as AISI 316 or AISI 304 stainless steel, aluminium, HDPE(High-Density Poly Ethylene), and FRP (Fiberglass-Reinforced Polymer) is essential. These materials withstand moisture and humidity without corroding or warping.

Adjustable feet accommodate slightly inclined floors for proper water drainage, while adequate space above and between racks allows easy maintenance and tank changes. Long-term durability reduces the need for frequent maintenance or replacement. Focusing on these aspects allows avoiding disruptions and maintaining a stable environment for zebrafish breeding, ultimately helping get reliable results for each research project.

Learn more about Luxaqua’s fish tank rack systems

2. Advanced automated filtration for zebrafish husbandry

Filtration systems are crucial for maintaining water quality in zebrafish tanks, mimicking their natural habitat. Local tap water may contain pollutants unsuitable for zebrafish. In any case, reverse osmosis water, remineralised with artificial salts, is the ideal solution to provide the required water quality regarding minerals and conductivity (200µS/cm² +/-10 %).

Open vs. closed circuits

Closed recirculating systems are the best choice for zebrafish breeding due to their superior control over water parameters. These systems continuously recycle water through mechanical and biological filters, maintaining optimal conditions for zebrafish health and breeding. Maintaining optimal water parameters is also a way to ensure the reliability of the results.

In contrast, open systems have a continuous water flow, making them simple and easy to manage but dependent on high-quality inlet water and costly due to water and heating needs. Closed stagnant systems change water at intervals andare inexpensive and low-maintenance. However, they result in poorer water quality and aeration over time. Overall, closed recirculating systems provide aquatic research facilities with the best long-term stability and efficiency.

Types of filters and their benefits

In closed recirculating systems, also called life support systems, different types of filters work together to ensure optimal water quality:

  • Mechanical filtration removes suspended organic matter.
  • Biological filtration supports bacterial colonies for nitrification

Mechanical filters, placed ahead of biological filters, remove large insoluble (or not yet dissolved) particles, increasing the efficiency of the subsequent filtration stages and preventing clogging. These filters are often foam blocks, cartridge filtersor pocket filters. They vary in coarseness to capture particles of different sizes.

Biological filters play a critical role in removing toxic dissolved nitrogenous compounds. Materials like ceramics or food-grade plastics, such as bio balls, provide a habitat for beneficial bacteria that break down harmful substances. These filters are essential for maintaining water quality in zebrafish tanks by converting toxic nitrogen waste products like ammonia and nitrite into less harmful nitrate compounds and then diluted in purified water (reverse osmosis, see below) to a non-toxic concentration. Examples of effective biological filter materials include bio-balls (easy to clean), perlon wadding (changed every 3 months), expanded clays (good lifespan), and pozzolan (cost-effective).

Finally, protein skimmers, or foam fractionators, complement biological filters by catching and removing dissolved organic matter through the action of tiny bubbles produced by a high-pressure air intake. Placed ahead of biological filters, they help their efficiency by removing a significant amount of organic matter and reducing their load.

Automated life support system

Automated filtration systems are essential for maintaining optimal conditions in zebrafish breeding tanks. They regulate parameters such as temperature (ideally 26/28°C – 79/82°F) in the case of zebrafish), pH, and conductivity. Maintaining optimal temperatures promotes high metabolism, hence quality spawning.

Water is collected in a sump tank before being processed through filters and other equipment. Sensors monitor water quality and then activate actuators to adjust conditions. These actuators are sets of pumps and automatic valves. Pumps supply fresh tap water or osmosis water. The sump’s water level sensor ensures clean water replenishment and evaporation compensation.

Lighting is also essential to recreate natural spawning conditions. Automated lighting schedules regulate zebrafish biological rhythms, including reproduction. Security sensors for water levels and leakage detection prevent potential issues, ensuring zebrafish live in safe conditions.

Learn more about Luxaqua’s aquatic life support systems

3. Secure water treatment system for optimal zebrafish larvae development

Water quality is especially critical during the larval stage of zebrafish development. Ensuring larvae grow in contaminant-free water can significantly impact their growth and survival rates. Reverse osmosis systems allow precise water quality control by adding mains water, salts, and other adjustments.

Biosecurity and wastewater management

Proper wastewater management is essential to prevent environmental pollution and maintain biosecurity in zebrafish breeding facilities. Biosecure waste management systems mitigate the risks of contamination and disease spread. Effluent treatment is crucial because animal facilities often house non-native species or genetically modified organisms (GMOs). Effective methods include decantation, finefiltration, chlorination, ozonation, heating and UV sterilisation.

Learn more about aquatic animal health management

Purification and disinfection

Reverse osmosis (RO) is a highly effective method for purifying water, crucial for the delicate developmental stages of zebrafish larvae. RO systems use high-pressure pumps to push water through a semipermeable membrane, which acts as a molecular-level filter. This process allows only water molecules to pass through while blocking larger ions, molecules, minerals, and impurities, ensuring a clean and stable environment for zebrafish larvae. The reverse osmosis system can be completed by a pre-filter, a water softener and a heating system to improve efficiency.

Additionally, UV treatment protects against bacteria and viruses, maintaining water safety. UV light halts bacterial multiplication by causing mutations, thereby preventing the spread of diseases among aquatic animals. The recommendation for UV exposure is 40 mJ/cm2.

Learn more about reverse osmosis systems

4. Reliable monitoring system for successfully breeding zebrafish

Continuously monitoring water parameters (pH, conductivity, temperature, and dissolved O2, at least) is essential for successfully breeding zebrafish. Reliable monitoring systems enable researchers and zootechnicians to maintain optimal conditions and swiftly address issues.

Remote control and monitoring

Modern monitoring systems enable remote control of environmental parameters and actuators, ensuring researchers can maintain optimal conditions from anywhere. Luxaqua’s fish tank monitoring solution, LXA_DataTech, integrates seamlessly with aquatic life support systems and various sensors. It can send commands to pumps and automatic valves, ensuring total control of the facility system. All sensors and actuators are wired to a centralised controller managed by our software. LXA_DataTech can monitormultiple fish tank racks to accommodate breeding and/or research protocols.

Learn more about Luxaqua’s fish tank monitoring systems

Trend analysis

Advanced monitoring systems can help you analyse trends in water parameters, helping to anticipate and prevent potential problems before they affect zebrafish. Luxaqua’s LXA_DataTech software logs, displays, and analyses real-time data, providing a comprehensive overview of the breeding tank conditions. It enables researchers with critical information, making it easier to manage multiple breeding tanks effectively and ensure optimal conditions for zebrafish.

Learn more about Luxaqua’s fish tank monitoring software

5. Efficient information management for tracking zebrafish colonies

Efficient information management is crucial for tracking zebrafish colonies, lineage and research projects. Proper data management ensures compliance with regulations and enhances overall research facility efficiency. Keeping zebrafish colonies healthy involves meticulous data processing and a robust plan addressing nutrition, water quality, biosecurity, and quarantine.

Compliance with authorities

Maintaining accurate records is necessary to comply with regulatory requirements. Information management systems help ensure all data is documented and accessible for inspections or audits. Compliance with regulations and a commitment to animal welfare should be viewed as opportunities for aquatic research centres to improve practices and advance scientific knowledge while upholding their ethical responsibility of care.

Research project tracking

Efficient information management systems are essential for tracking research projects, fish colonies, lineage, quantity, health status, and water parameters. These systems streamline data collection and analysis. Advanced IT tools, such as LXA_Fishlab, simplify monitoring the health of aquatic animals, reducing errors, increasing survival rates, and making regulatory compliance more manageable. With robust analytics and reporting, these tools provide reliable data collection and support continuous improvement in research efforts.

Learn more about Luxaqua’s zebrafish information management software

For more information on optimising your zebrafish breeding tanks or the necessary equipment (hardware and software) for breeding other aquatic species, don’t hesitate to contact us to explore our solutions for aquatic research centres.

Fish tank monitoring system

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