Introduction to Fish Breeding: A Beginner's Underwater Adventure

Introduction to Fish Breeding: A Beginner's Underwater Adventure

Vanessa LeRoux


Welcome to the captivating world of fish breeding, a fascinating journey that unfolds right in your home aquarium. From the delicate dance of courtship to the moment of spawning, and finally, the arrival of tiny fry, breeding fish is an adventure that's as educational as it is rewarding. Different fish species' diverse reproductive strategies and breeding habits offer a glimpse into an underwater mystery teeming with intriguing variations.





Fish breeding isn't just about science; it's also a vibrant splash of excitement in your everyday life. Whether you're a seasoned aquarist or a curious beginner, breeding fish offers a world of discovery. It's a hobby that requires patience, care, and a keen eye, but the rewards are well worth it. So, are you ready to dive in? Let's embark on this exciting journey together, exploring the wonderful world of fish breeding.





Two orange tropical fish 'kissing'




Decoding Fish Reproduction: A Closer Look





How do fish reproduce?





Nearly all fish reproduce sexually, and most species have separate sexes. Simultaneous hermaphrodites - without separate sexes, avoid self-fertilization by producing sperm and eggs at different times.





You can typically find various fish species at your local fish stores that employ diverse reproductive methods.





mouthbrooding cichlid releases fully formed young fry




Exploring Fish Reproductive Strategies: From Egg Laying to Mouthbrooding





Egg-laying species: These fish have a range of egg deposition strategies. Some scatter their eggs randomly, others bury them for protection, while some carefully place them in specific locations.





Live-bearing species: These fish are unique in that they give birth to offspring that are already fully developed.4





The following are the scientific names for these reproductive methods:





Oviparous fish





Each fish typically produces a large number of gametes. In most fish species, fertilization takes place externally. These fish are oviparous. Eggs are laid, and embryos develop outside the mother's body. Trout, tuna, puffer fish, carp or sea bass belong to this group of fish.





Viviparous Fish





Viviparous fish give birth to live young; the eggs develop whilst receiving nutrition from the parent.8 There are about 500 freshwater viviparous species.





Ovoviviparous Fish





Eggs are laid, and embryos develop outside the mother's body. In a minority of fish, including sharks, eggs develop inside the mother's body but without nourishment from the mother. These fish are ovoviviparous. Examples are Guppies and Platies and the Tiger Shark!





Spawning Fish





In many species of fish, a large group of adults come together to release their gametes into the water at the same time. This is called spawning. It increases the chances that fertilization will take place. It also means that many embryos will form at once, which helps ensure that at least some can escape predators.





With spawning, there is no way for fish parents to know which embryos are their own. Therefore, fish generally don't provide any care to their eggs or offspring. Salmon and Tetras are spawning fish.





Mouthbrooding Fish





Some fish species carry their fertilized eggs in their mouth until they hatch. This is called mouthbrooding. Cichlids in Lake Malawi, Lake Tanganyika and Lake Victoria are mouthbrooders.5





Image showing the difference between a female and male platy




Understanding Fish Gender: The Impact of Nutritional and Environmental Conditions





It's crucial to be able to distinguish between male and female fish. Usually, the male fish has brighter colours and pronounced fins, while the female fish might be larger and less colourful. Visiting your local fish stores or consulting with experienced fish breeders might offer helpful insights on fish mates.





It's important to keep in mind that fish under poor nutritional or environmental conditions might not exhibit gender differentiation. "Reproductive function may be limited in fish not receiving appropriate nutrition or space. When resources are scarce, fish will forgo reproductive function in order to survive. Fish in situations that are being stunted due to space or dietary restrictions are unlikely to reproduce and, therefore, do not show any external signs of gender differentiation"3







Optimizing Nutrition for Successful Fish Breeding





A balanced diet is crucial for the overall well-being of your adult fish, especially those preparing for breeding. A mix of live and frozen foods can provide their diverse and nutrient-rich diet. Unlike other food types, these foods are usually consumed entirely, preventing significant tank pollution.





Live Foods: Stimulating Natural Hunting Instincts





Live foods are particularly beneficial for fish. They provide essential nutrients and trigger the fish's natural hunting instincts. This leads to increased consumption, making live foods an excellent choice for fish that are underfed or still growing.





The Role of Live Foods in Fish Breeding





The energy demands of reproduction are high, and live foods can help meet these needs. They are often used to quickly condition fish for breeding due to their nutritional value and ability to stimulate increased consumption.





Choosing the Right Live Foods: Factors to Consider





Live foods can include a variety of organisms, such as worms and insects. However, they come with their own set of considerations. These include the size of the food, the care needed to maintain it, and its availability. Therefore, choosing the live foods that best suit your aquarium's needs and your fish's dietary requirements is important. It's recommended that both the female and the male fish get fed live brine shrimp; if live is not available, then frozen will also do the trick.





How Much to Feed Your Breeding Fish





"Provide them with an abundance of high-protein food, feeding more often than you would normally feed your community aquarium fish, typically three times daily. You are preparing them for breeding, so they must have sufficient energy in their bodies for their own maintenance and growth as well as to produce eggs."1





square tank with neon tetras swimming about.




Tank Size and Safe Water Conditions Geared for Success





Size It Up: Choosing Your Breeding Aquarium





The dimensions of the breeding aquarium are contingent upon the type of fish. Species that are larger or breed collectively require more room than smaller species or those that mate in pairs. "We find that the 37-litre aquarium is both inexpensive, easy to store, easy to get supplies for and is enough room for you to breed almost any beginner fish species."1 The appropriate spawning substrate or decor that is necessary will depend on the method of egg-laying of the fish species you choose to breed.







Achieving the Perfect Water Conditions for Breeding Fish





Water conditioner removes harmful substances like chlorine and heavy metals, ensuring the water in your breeding tank is safe for fish breeding. Nutrient levels like ammonia, phosphates and nitrates need to be low. It's also important to note the general hardness of the water.





"For most species, it is imperative that the water be in very good condition. The water parameters may also matter as some species refuse to mate except if the pH, temperature, and other parameters are within certain values. Research your fish to see if they are picky or not. If they are picky, try your best to offer them the water parameters they like. Even if the fish you are trying to breed are not especially picky, you should still make sure that the water condition in your breeding tank is as high as possible."2







Stimulating Fish Breeding: The Impact of Warmer Water and Longer Daylight Hours





Most fish species are stimulated to breed by environmental changes. Two key factors that often contribute towards fish breeding are rising water temperatures and increased daylight hours. You can simulate these changes in your aquarium to encourage your fish to breed.





Maintaining the correct water temperature is crucial. Most fish species breed in warmer water, so an adjustable heater can help create the right conditions for the breeding season.





Alongside temperature, daylight hours also play a significant role. Simulating longer daylight hours can be achieved by using a timer to control the light in your aquarium. This can further encourage your fish to breed.





By carefully controlling these two environmental factors, you can effectively stimulate the breeding season in your aquarium.







The Role of Spawning Materials in Fish Reproduction





Creating a conducive environment for fish breeding involves more than just maintaining water quality and temperature. It also requires setting up the tank to mimic the natural breeding habitats of the fish species you're working with. This is where the provision of appropriate spawning materials comes into play.





Spawning materials can vary widely depending on the species of fish. Here are some common types:





Plants: Many fish species prefer to lay their eggs on the leaves of aquatic plants. Plants not only provide a suitable surface for egg deposition but also offer a hiding place for the fry once they hatch. Plants like Java Moss, Anubias, and Amazon Sword are popular choices for breeding tanks.





Spawning Mops: These are bundles of yarn or synthetic fibres that simulate the dense vegetation found in many natural fish habitats. Fish such as killifish and some species of tetras scatter their eggs amongst such vegetation. Spawning mops provide a similar environment within the breeding tank.





Flat Rocks: Certain species, especially many types of cichlids, prefer to lay their eggs on flat surfaces. Flat rocks placed at the bottom of the tank can provide an ideal spawning site for these fish.





Breeding Cones: Breeding cones are typically used by Discus. These fish prefer to lay their eggs on a vertical surface, and a breeding cone provides just that. They are usually made of ceramic or plastic and can be easily cleaned and reused.





Cat fish and breeding cave<br>




Breeding Caves: Some fish, like certain types of cichlids and catfish, are cave spawners. They prefer to lay their eggs in a secluded, protected space. Providing caves or similar structures can encourage these fish to breed. Caves can be made from various materials, including rocks, clay pots, and PVC pipes.





Remember, the choice of spawning material should be guided by the specific breeding habits of the fish species you're working with. Researching and replicating these habits in your breeding tank will increase your chances of successful fish breeding.





fish fry swimming about on a black background




Breeding Fish in Your Existing Tank: A Practical Approach





It's safe and possible to breed fish within your existing tank. These systems allow for safe and practical breeding. In certain species, adult fish may pose a threat to their eggs or young. In such cases, it's essential to use a divider or a breeding net to safeguard the vulnerable fry until they are strong enough to fend for themselves. The same applies if the breeding pair exhibits aggressive behaviour towards each other.





Dividers are used to isolate a pregnant mother fish to keep her safe. The most important use of these is to keep the fry safe from getting hurt or eaten by their parents or other fish in the aquarium.







The Boyu NB-3202A Aquarium Net Breeder





The Boyu NB-3202A aquarium net breeder is a great example of this: saving time and money by allowing separation and isolation in your existing aquarium with no need for purchasing a separate breeding tank. The durable plastic and mesh net breeder comes with two separate compartments separated by a grill that allows the safe filtering through of larger eggs.





The dual net breeder with six suction cups is easy to assemble, fit, clean, and attach to your tank's glass sides. It ensures the safety of your newborn fish by separating them from the possible predators and dangers lurking in your aquarium. With the hatchery's two-storey layer system, you can use it for pregnant and spawning fish. Remember to install the net breeder in such a way that the water level is below the top frame.





Also ideal for segregating maturing fry, injured or aggressive aquarium inhabitants without purchasing a breeding tank. Isolating sick fish is not recommended, as the aquarium water could still be contaminated. Note that rinsing with aquarium water is required prior to use. Dimensions: 14 x 14 x 28cm.





Preparing the Fish for Breeding:





It's beneficial to keep males and females apart for certain species, ideally with a transparent barrier between them. This allows them to see each other constantly without physical contact. This arrangement heightens their desire to breed when the opportunity arises.





closeup of a guppy against a black background




Breeding for Beginners: Easy-to-Breed Fish





Ready to splash into the exciting world of fish breeding? Great! Let's introduce you to some of the easiest and most rewarding fish species to start your breeding journey with. From the vibrant Guppies to the fascinating Firemouth Cichlids, these species are known for their unique breeding habits and manageable care requirements. As a novice aquarist looking to expand your aquatic family, these fish offer a satisfying breeding experience. So, let's meet these underwater stars and learn about their breeding habits.





Guppies: Guppies are a favourite among breeders because they're low-maintenance, breed quickly, and are lively, making them fun to watch. They don't need specific breeding conditions, just a clean habitat and a ratio of one male to three female guppies. The young, or fry, are born wholly developed and can fend for themselves from the get-go.





Swordtail: This freshwater fish, one can easily mistake for a Platy, is one of the best choices for a pet fish, especially for beginners. Its colours vary. Caught from the wild, the body of the swordtail is generally olive green with yellow and red streaks along its two sides.





orange mollies swimming on black background




Mollies: Mollies are known for their live-bearing reproduction, capable of producing more than a hundred offspring at once. If you plan to breed Mollies, you'll require one male for several females and a separate tank to accommodate the pregnant female. It's crucial to promptly separate the newborns from their parents, as Mollies tend to consume their offspring.





breeding chart for platies




Platies: Breeding Platies is relatively straightforward, but they tend to prey on their own young. Once the female Platy is confirmed to be pregnant, she should be moved to a separate nursing or breeding tank. After she gives birth, it's important to promptly remove her to ensure the safety of the fry, allowing them to thrive without the threat of being consumed.





Zebra Danios: Zebra Danios are an excellent choice for beginners in fish breeding. They require a suitable breeding tank and appropriate conditions for successful breeding. After laying their eggs in the breeding tank, the adult Zebra Danios should be transferred back to their usual habitat to ensure the safety and survival of the eggs.





Firemouth Cichlids: Firemouth Cichlids are relatively low-maintenance when it comes to breeding. They should be housed in a tank of at least 190 litres, and it's recommended to raise multiple pairs together so they can form pairs naturally as they mature. There's no need for a separate breeding tank for these fish. Unlike some species, Firemouth Cichlids tend to care for their young rather than preying on them.6 To learn about other great fish species for beginners, click here.





pink and purple fish swims through the aquarium




Breeding Aquarium Fish: More Than a Hobby, It's a Journey into Life's Wonders





Embarking on the journey of breeding aquarium fish is akin to diving into a vibrant underwater world filled with wonder and discovery. It's a process that requires careful planning, a keen eye, and a nurturing touch. Yet, the rewards are immeasurable. As you witness the miracle of life unfolding right in your aquarium, from the first flutter of tiny fins to the growth of young fish, you'll gain a profound appreciation for the intricate dance of nature.





Breeding fish is not just about increasing the population in your tank. It's about participating in a cycle of life that's as old as the oceans themselves. It's about understanding the delicate balance of ecosystems and the fascinating diversity of aquatic life. And most importantly, it's about the joy and satisfaction that comes from nurturing life.





Whether you're a novice aquarist or a seasoned fish enthusiast, the world of fish breeding offers endless opportunities for learning and growth. So, don your explorer's hat, roll up your sleeves, and dive into this exciting adventure. Remember, every great aquarist started with a single fish and a dream. Who knows? You might just be the next great fish breeder!





And remember, if you ever find yourself in uncharted waters, don't hesitate to seek advice from experienced breeders or staff at your local fish store. After all, every successful journey is made easier with a little help from friends. Happy breeding!





neon tetra gains black backdrop




Frequently Asked Questions





How do I create the right conditions for fish breeding?





Environmental conditions such as water temperature and its chemical and mineral composition can significantly affect fish breeding. You might need a dedicated heater to raise the tank's temperature or alter the water's fundamental properties to make it softer. For instance, if you're breeding Discus or similar species, you must adjust the water temperature to fall within a range of 28–31 °C. Additionally, maintaining a pH level of 6-7 and ensuring the light levels are moderate to low is also crucial for successful breeding.





How do I care for the fry after they hatch?





Upon hatching, the fry are initially nourished by a sizable yellow egg sac attached to them. This sac serves as their food source for the initial few days. However, once the egg sac is depleted, it's your responsibility to provide them with suitable food. Options for feeding the fry include liquid egg yolks, ground fish flakes, plankton, and algae. As the fry mature and increase in size, their diet can be upgraded to include more substantial live foods such as brine shrimp and micro worms.





What is a spawning tank, and why is it important?





A spawning tank is a distinct aquarium used specifically for the purpose of breeding. By isolating the parent fish in this tank, they are more inclined to mate. Additionally, the separate environment of the spawning tank allows you to fine-tune the conditions necessary for breeding without affecting the rest of your fish population that isn't involved in the breeding process.





What kind of diet should I provide for the parent fish during the breeding process?





While preparing your fish for breeding, it's essential to provide them with a diet high in nutrients and protein. This kind of diet not only promotes their overall health but also enhances their fertility, increasing the chances of successful breeding. Due to their size and dietary preferences, many common aquarium species favour live food such as fresh or frozen brine shrimp. Including such live food in their diet not only meets their nutritional needs but also stimulates their natural feeding behaviours, contributing to their overall well-being.





How do I determine the sex of the fish I want to breed?





While the biological characteristics can differ significantly among various fish species, there are some general features to identify. For instance, female Cichlids often possess rounder bodies and less noticeable vents, whereas males typically exhibit brighter colours and might even have a small bump on their heads. If you find it challenging to differentiate, it's advisable to seek advice from an aquatic vet or a specialist in fish breeding.7





VI. Resources





1 - https://www.thesprucepets.com/breeding-aquarium-fish-basic





2 - https://www.ratemyfishtank.com/blog/breeding-freshwater-fish





3 - https://cafishvet.com/betta/how-to-tell-the-gender-of-a-fish/





4 - https://en.wikipedia.org/wiki/Fish_reproduction





5 - https://bio.libretexts.org/Bookshelves/Introductory_and_General_Biology/Boo





6 - https://www.fishtankreport.com/easiest-fish-to-breed/





7 - https://www.wikihow.com/Breed-Fishhttps://www.wikihow.com/Breed-Fish





8 - https://en.wikipedia.org/wiki/Category:Viviparous_fish