How to Care for Prawns: A Complete Guide
Prawns are fascinating creatures that can bring life and excitement to any aquarium. Their unique appearance and interesting behaviors make them a popular choice for aquarists. Whether you’re a beginner or a seasoned hobbyist, understanding how to properly care for prawns is essential for creating a thriving environment for these animals.
In this complete guide, we will cover everything you need to know about prawns, from their habitat and tank setup to feeding, breeding, and common health issues. With the right care, prawns can thrive in your aquarium and become an intriguing addition to your aquatic ecosystem.
What Are Prawns?
Prawns are a type of crustacean found in both saltwater and freshwater environments around the world. They belong to the suborder Natantia and are closely related to shrimp, although there are notable differences between the two. Prawns tend to have a larger body and longer legs than shrimp, and their gill structure and physical appearance differ slightly.
In the aquarium hobby, prawns are most commonly found in freshwater environments, although there are species that live in brackish or saltwater. Some of the most common freshwater species of prawns include the Macrobrachium species, such as the Macrobrachium rosenbergii (Giant River Prawn), which are often kept in aquariums. They are known for their fascinating behaviors, which include scavenging for food, digging, and sometimes even interacting with other tank inhabitants.
Prawns are typically peaceful creatures, although larger species may exhibit territorial behavior or aggression toward smaller tankmates. Most species of prawns are omnivores, feeding on a combination of plant material, detritus, and small invertebrates.
Setting Up the Perfect Prawn Tank
To ensure your prawns live a long, healthy life, it is essential to provide them with a proper habitat that meets their needs. Proper tank setup, water conditions, and tankmates are all key to creating a successful prawn aquarium.
1. Tank Size
The size of the tank is an important consideration when keeping prawns. While they don’t require a massive tank, it’s essential to give them plenty of space to explore, forage, and hide. A minimum tank size of 20 gallons (75 liters) is recommended, especially for larger prawn species like the Macrobrachium rosenbergii. Smaller species can thrive in tanks as small as 10 gallons, but bigger is always better when it comes to prawns.
A larger tank also helps to maintain water quality and allows for better distribution of food and space. Overcrowding can lead to stress, poor water quality, and aggression among prawns and other tankmates.
2. Water Parameters
Prawns are highly sensitive to water quality, so maintaining proper water parameters is essential. Here are the key water parameters to keep in mind:
- Temperature: Most freshwater prawns thrive in a temperature range of 72°F to 78°F (22°C to 26°C). Some species may tolerate slightly cooler or warmer water, but it’s best to keep the temperature stable to avoid stressing the prawns.
- pH: Prawns generally prefer a slightly alkaline to neutral pH level, ranging from 6.5 to 8.0. Ensure that the pH remains stable, as large fluctuations can harm your prawns.
- Hardness (GH and KH): A general hardness (GH) of 6-12 dGH and a carbonate hardness (KH) of 3-10 dKH is ideal for prawns. Some species may prefer slightly softer or harder water, so it’s important to research the specific requirements of the prawn species you are keeping.
- Ammonia/Nitrite: Ammonia and nitrites are toxic to prawns, so levels should be maintained at 0 ppm at all times. Ensure your filter system is efficient and that the tank is fully cycled before introducing prawns.
- Nitrate: Nitrate levels should be kept below 20 ppm. While nitrates are less toxic than ammonia and nitrites, high levels can stress prawns and affect their overall health.
Regular water testing with a reliable test kit is important to monitor and adjust the water parameters. Frequent water changes (about 20-25% weekly) will also help to maintain water quality.
3. Filtration
A proper filtration system is crucial to keep the water clean and free from harmful toxins. A sponge filter is often the best choice for prawn tanks, as it provides gentle filtration without creating strong water currents. Prawns are not strong swimmers, and they can be easily stressed or injured by fast-moving water.
Sponge filters also have the added benefit of growing beneficial bacteria that help break down waste and maintain a healthy biological filtration system. It’s important to make sure the filter’s intake is protected with a sponge or mesh to prevent prawns from getting sucked in.
4. Substrate and Decorations
Prawns enjoy digging and foraging, so a soft substrate such as fine gravel, sand, or a nutrient-rich substrate is ideal. Sand is a good option because it is gentle on their sensitive bodies and provides an environment in which they can burrow and search for food. If you choose gravel, make sure the grains are smooth and not too sharp.
Providing plenty of hiding spots and shelters is also essential for prawns, as they enjoy seeking out secure areas. Decorations such as rocks, driftwood, PVC pipes, and live plants can create hiding spots and encourage natural behavior. Plants such as Java Moss, Anubias, and Java Fern are great choices for prawn tanks, as they offer shelter and food in the form of biofilm.
5. Lighting
Prawns do not require intense lighting, but moderate lighting helps create a natural day-night cycle and encourages plant growth. A good lighting system will also promote algae growth, which prawns can feed on. A light period of 8-12 hours per day is generally sufficient.
6. Tankmates
Prawns are typically peaceful, but they can be territorial or aggressive toward smaller tankmates, especially when they molt or feel threatened. When choosing tankmates, it’s important to select species that won’t harass or prey on the prawns. Compatible tankmates for prawns include peaceful fish, snails, and other invertebrates.
Species such as neon tetras, guppies, or small catfish like Corydoras are often good choices for prawn tanks. Avoid larger fish or aggressive species that may try to eat or harm the prawns. Similarly, be cautious with other invertebrates, such as crabs or large snails, that may compete for food or space.
Feeding Prawns
Prawns are omnivores and will consume a variety of foods. Their diet typically consists of algae, detritus, and small invertebrates, but they can also be fed commercial foods, such as pellets and frozen foods, to ensure they get all the necessary nutrients.
1. Algae and Biofilm
In a well-established aquarium, prawns will graze on algae and biofilm that form on surfaces, rocks, and plants. If your tank has live plants and a healthy ecosystem, this can be a primary food source for your prawns.
2. Vegetables
Prawns enjoy a variety of vegetables, such as blanched zucchini, spinach, lettuce, and carrots. These vegetables provide important nutrients and fiber, and prawns will happily scavenge and eat them. Be sure to remove uneaten vegetables after a few hours to prevent them from decomposing in the tank.
3. Protein
Prawns are also scavengers and can benefit from occasional protein in their diet. You can feed them small amounts of frozen brine shrimp, bloodworms, or daphnia. Commercial shrimp or prawn food, such as pellets, can also be used to ensure they receive a balanced diet.
4. Feeding Schedule
It’s important not to overfeed your prawns, as leftover food can degrade water quality. Offer small portions of food once or twice a day, and remove any uneaten food after a few hours. Prawns are natural foragers and will often scavenge throughout the tank for food, so don’t be concerned if they seem to be eating less during feeding times.
Breeding Prawns
Prawns are relatively easy to breed in the right conditions. Some species, such as the Macrobrachium rosenbergii, can grow quite large and breed in captivity with minimal intervention. However, breeding prawns requires a bit of patience and attention to detail.
1. Sexing Prawns
Sexing prawns can be a bit tricky, but it’s possible once they reach maturity. Female prawns are typically larger than males and often have a wider abdomen. Male prawns may have more slender bodies and larger pincers (in certain species). In some species, females may also exhibit a distinctive coloration or markings.
2. Mating and Egg Carrying
Once female prawns mate, they will carry the fertilized eggs under their abdomen. Depending on water temperature, the eggs will hatch in 2-4 weeks. After hatching, the tiny larvae will gradually transform into juvenile prawns that resemble miniature adults.
3. Raising Juvenile Prawns
Juvenile prawns are delicate and require special care. Make sure the water quality is pristine and provide plenty of food for them to forage on, such as algae, fine particles of food, and biofilm. Young prawns are vulnerable to predation, so it’s essential to provide adequate hiding spots and keep the tank free from larger or more aggressive species.
Common Health Issues in Prawns
While prawns are generally hardy, they can still experience health issues if not properly cared for. Below are some common health problems and how to prevent or treat them:
1. Molting Problems
Prawns must molt (shed their exoskeleton) in order to grow, and problems can arise if they are stressed, malnourished, or in poor water conditions. If a prawn has difficulty molting, it may become stuck in its old exoskeleton, which can be fatal. Ensuring that your prawns have a balanced diet, stable water conditions, and plenty of calcium for shell development will help prevent molting issues.
2. Infections and Disease
Prawns can develop infections or fungal diseases, particularly if they are stressed or exposed to poor water quality. If you notice white spots, lesions, or lethargy, it’s important to address the water quality and remove any infected prawns to prevent the spread of disease. Isolating sick prawns in a quarantine tank can help prevent contamination.
3. Stress and Aggression
Prawns can become stressed if they are kept in overcrowded tanks, exposed to sudden temperature changes, or kept with incompatible tankmates. Stress can lead to a weakened immune system, molting problems, and even death. Maintaining stable water conditions and providing ample hiding spots will help reduce stress.
Conclusion
Caring for prawns can be a rewarding experience, and with the right care, these fascinating creatures can thrive in your aquarium. From setting up the ideal tank to feeding, breeding, and troubleshooting health issues, following the advice in this guide will help you create a healthy and happy environment for your prawns. Whether you’re keeping them for their beauty, scavenging abilities, or breeding potential, prawns make an excellent addition to any freshwater tank.
