Aquaponics - What is it?
As part of our projects, we work with aquaponic systems. Here we explain what it actually is and what advantages this sustainable method offers.
Functionality
Aquaponics describes a sustainable agricultural method that combines fish farming (aquaculture) with the cultivation of plants in hydroponics (without soil). It is a closed-loop system where the water from fish farming is reused for plant cultivation. The fish excretions contain toxic ammonia, which is converted by bacteria into nitrate, a plant nutrient. The fish excretions serve as fertilizer for the plants, and the purified water flows back into the fish tank.
For our aquaponic systems, we have opted for the “ebb and flow” irrigation technique. In this method, the plant bed is filled with a substrate into which the plant roots grow. The plant bed is periodically flooded with water from the fish tank for irrigation. This water contains fish excretions, including toxic ammonia. Bacteria living in the hydroponic system are capable of converting this into nitrate. The nitrate is then absorbed by the plants, and the water is biologically purified. Fish, bacteria, and plants operate in synergy: fish excretions serve as natural fertilizer for the plants after bacterial conversion. Simultaneously, the substrate acts as a mechanical filter, removing solid residues from the water so that it can be returned directly to the fish tank without an intermediate stage. We use volcanic gravel as a substrate.
In aquaponics, robust fish species are often kept. Tilapia (cichlids) originate from Africa, have low feed requirements, and adapt well to fluctuations in environmental conditions. For hydroponics (plant cultivation in nutrient solution), primarily edible crops are produced. A wide variety of plants are suitable for this cultivation method. Many vegetables and herbs even grow faster and more efficiently in hydroponics.
Aquaponics (aquaculture and hydroponics)
ADVANTAGES OF AN AQUAPONIC SYSTEM
Due to the efficient water cycle, the daily fresh water requirement can be significantly reduced compared to traditional soil-based cultivation. For instance, one kilogram of tomatoes now only requires 35 liters of water instead of up to 180 liters.
Since aquaponics operates independently of soil, the soil resource is relieved, and a system can be installed in various locations.
Environmental parameters can be flexibly adjusted, creating a controllable environment. This promises food security in a time when climate change threatens harvests.
Furthermore, the system operates emission-free: the carbon dioxide emitted by the fish is converted into oxygen by the plants.
Due to the reduced fertilizer usage, aquaponics is among the most resource-efficient cultivation methods
The whole process works without weeding and watering!
