Seasonal variations significantly impact fish farming, especially catfish farming. As a fish farmer, understanding the 8 effects of hot season on fish farming is crucial for maintaining a healthy and productive fish farm.
One of our valued farmers reached out to us with a concern: he noticed excessive bubbles on the surface of his pond. After ruling out any aeration system in use, I explained that this was a sign of low oxygen levels, a common issue during the hot season.
With many regions, especially in West Africa, entering the hot season, it is vital to discuss the effects of high temperatures on catfish farming and how to manage these challenges effectively.
The 8 Effects of Hot Season on Catfish Farming
1. Reduced Dissolved Oxygen Levels
Oxygen is essential for fish survival. During hot weather, dissolved oxygen levels in ponds drop significantly, making it harder for catfish to breathe. This can lead to stress, erratic swimming, gasping at the surface, and even mass fish deaths, particularly at night when oxygen levels are at their lowest.
Low oxygen levels also slow digestion and reduce feed conversion efficiency, resulting in poor growth rates. The reduced dissolved oxygen levels are one of the 8 effects of hot season on fish farming.
2. Increased Ammonia and Nitrite Levels
High temperatures speed up the decomposition of organic waste, leading to a rise in toxic ammonia and nitrite levels.
- Ammonia burns fish gills, making breathing difficult and causing stress.
- Prolonged exposure weakens the immune system, increasing the risk of diseases.
- Nitrite poisoning affects blood oxygen levels, leading to a condition known as “brown blood disease.”
3. Higher Metabolism and Increased Feed Demand
Warm water increases fish activity, requiring more food for energy. However, overfeeding leads to excessive waste, further degrading water quality. Poor water conditions stress fish and may result in slow growth, even with increased feeding.
4. Heat Stress and Increased Disease Susceptibility
Heat stress weakens the immune system, making catfish more prone to infections. Bacterial diseases like columnaris (cotton wool disease) and fungal infections are more common in warm conditions.
External parasites such as flukes and lice also thrive in hot water, further impacting fish health. Understanding the 8 effects of hot season on fish farming and how to manage them can help mitigate these challenges.
5. Low Water Levels and Increased Evaporation
High temperatures cause rapid water evaporation, reducing pond levels. Shallow water heats up faster, exacerbating oxygen depletion and concentrating harmful substances like ammonia and nitrite.
Evaporation is not only common in fish ponds during the hot season but also common in natural water bodies such as dams, rivers, lakes, and others.
6. Algae Blooms and Oxygen Crashes
Excessive heat promotes rapid algae growth. At night, algae consume large amounts of oxygen, causing dangerous oxygen crashes.
Some algae species release toxins that can harm or kill fish. As algae decompose, they further pollute the water, increasing ammonia levels.
7. Increased Competition and Aggression Among Fish
Higher metabolism during hot weather makes fish more aggressive. This leads to injuries, fin nipping, stress, and even cannibalism. Injured fish are more susceptible to infections and diseases.
8. Poor Growth and Reduced Feed Conversion Ratio
Despite eating more, fish under heat stress experience reduced growth due to inefficient digestion and increased energy expenditure for respiration. This results in poor feed conversion and slow growth rates.
How to Manage the Effects of Hot Season in fish Farming
Now that we understand the 8 effects of hot season on fish farming, let’s explore effective strategies to mitigate the impact of hot weather on catfish farming.
After all, no matter how big a problem is, there will surely be a solution.
1. Increase Aeration to Maintain Dissolved Oxygen Levels
- Use aeration systems such as paddlewheels or air pumps to improve oxygenation.
- Avoid overstocking to reduce oxygen competition.
- Perform partial water changes with fresh, oxygen-rich water.
2. Control Ammonia and Nitrite Levels
- Reduce feeding rates during peak heat to minimize waste accumulation.
- Use biofilters or beneficial bacteria to break down ammonia.
- Regularly test water quality and remove excessive organic waste.
3. Adjust Feeding Strategies
- Feed fish during cooler times (early morning or late evening).
- Use high-quality floating feed to improve digestion and minimize waste.
- Practice responsive feeding—give small amounts at a time and observe their reaction to avoid overfeeding.
4. Minimize Stress and Prevent Diseases
- Maintain good water quality to reduce stress.
- Limit handling and transportation of fish during hot weather.
- Keep ponds clean and free of organic debris.
- Use natural immunity boosters like vitamin C and betel leaves.
5. Maintain Water Levels and Reduce Evaporation
- Regularly top up ponds with fresh water.
- Use pond liners to prevent seepage and maintain water levels.
- Provide shade using nets or artificial covers to reduce direct sunlight exposure.
6. Prevent Algae Blooms and Oxygen Crashes
- Avoid over-fertilizing ponds to limit excessive algae growth. If you are not clear, overfeeding your fish is fertilizing the pond since the leftover feed will decay and fertilize algae to grow.
- Remove decaying organic matter to prevent excess nutrient buildup.
- Use biological and mechanical filtration to maintain water quality.
7. Reduce Fish Aggression and Competition
- Maintain proper stocking density to prevent overcrowding. Always calculate well to ensure you do not stock your fish more than the capacity of your fishpond. But also remember that understocking also means loss since a lot of money will be left on the table. So struck a balance between overfeeding and underfeeding.
- Monitor fish for signs of aggression and injuries.
- Separate aggressive fish to prevent cannibalism and injuries. That is what we call sorting. You need to sort your fish according to sizes constantly.
8. Improve Growth and Feed Conversion Ratio
- Maintain optimal water temperature through shading and water management.
- Use high-protein feed to support efficient digestion and growth.
- Establish a consistent feeding routine based on fish activity levels. To make it simpler, you can install automatic feeders on your farm.
Install a Recirculating Aquaculture System (RAS) for Better Management
One of the best solutions to combat the effects of hot season in fish farming is installing a Recirculating Aquaculture System (RAS). This system provides both filtration and aeration, ensuring clean water and stable oxygen levels.
A well-designed RAS reduces harmful particles like leftover feed and fish waste, keeping the water fresh and reducing stress on fish. And on top of it, it adds oxygen to the fish to strive.
If you want to install a RAS on your farm, we can help.
Alternatively, you can learn how to build one yourself through our Comprehensive DIY Recirculating Aquaculture System Course. This step-by-step guide teaches you:
- How to source materials affordably
- How to assemble an efficient filtration and aeration system
- How to maintain water quality effortlessly
The course is priced at USD75 but the good news is that you get a Special Offer of 30% Discount Off as a cherished community member. You can enjoy the discount by using the code ‘faako’.
Enroll now and take full control of your fish farming operations.
Let’s grow our fish together, make more profit, and succeed in fish farming
