Aquaponics is a combination of hydroponics and aquaculture. Simply put, it’s the growing of plants and rearing of fish in the same space. This system can be customised to fit any kind of space; from that small space in your backyard to a greenhouse.
Aquaponics presents an integrated farming system whereby; waste from fish is used as fertiliser for plants and plants purify the water by removing the nutrients increasing oxygen concentration. Waste from fish contains nutrients which are essential for plant growth.
Aquaponic system. Image from http://organicdailypost.com/wp-content/uploads/2015/02/aquaponics-media-based.jpg
The set-up of the fish and plants represents a closed system such that;
- Water containing waste from the fish is pumped to the plants.
- Plants absorb nutrients from the water, in the process cleaning the water which is then pumped back to the fish.
What kind of fish can be used?
Any fish can be used. The only catch is that you’ll have to adhere to the requirements for the different types of fish. Types of fish used in some of the aquaponics systems here in Kenya are catfish, tilapia and trout. Catfish and tilapia do well in warm climates (temperature of between 25 to 28 degrees) whereas trout do well in cold climates (temperatures between 12 to 18 degrees). People in cold areas can make use of a greenhouse which will solve the temperature problem. It is important to ensure that both fish and plants have access to enough oxygen to prevent stress. Ensure that the water is clean to eliminate diseases in the fish which might be transferred to the plants or lead to the death of fish which might slow growth of plants due to inadequate nutrients.
What kind of plants can be grown using this system?
Strawberries are one of the common plants grown in Kenya using the aquaponics system. Other plants such as tomatoes, lettuce, herbs such as basil and mint can be grown using this system. However, it’s important to note that requirements differ from crop to crop.
- Maximizes space.
- Conserves water through recycling.
- It’s purely organic. Farmers are advised not to use chemical based pesticides since they will kill the fish since the water from the plants is recycled back to the fish.
- Increases income for farmers.
- Saves up on costs of fertiliser since it is a self-sufficient system.
Good news is that it’s being practised here in Kenya! Here’s a success story from a Kenyan farmer dealing in Aquaponics