How do aquaponic systems work?

There are two main ingredients to an aquaponics system

A Fish Tank: This can be a 55 gallon drum, aquarium, rain barrel, stock tank or a pond. Anything you can think of that will hold water.

A Plant Bed: You can use anything that will hold water and support the weight of your growing medium. Typically you’ll find it easier to position your plant bed higher than the water level in your fish tank.

The fish tank is linked to the plant bed and a pump circulates water through the system. When all aspects of the sytem are tuned appropriately, an ecosystem forms. The fish and the plants help each other grow, and bacteria makes this possible. Here is a simple diagram of how this works..

 The ecosystem:

An aquatic ecosystem is usually pretty self sufficient, but sometimes require a little human intervention. In your aquaponics system you should try to achieve a healthy balance of fish and plants which we will explain further down the page. When the system is balanced, the nitrification of fish waste will help you grow tastey produce, and fast!

You will feed your fish either pellet food or recycled plants from the plant bed. Some systems may even include a separate section for growing plants that can be used as fish food (like duckweed). As the fish eat and breathe they create waste which has a high ammonia content. When the fish water is pumped to the plant bed healthy and naturally occuring bacteria converts ammonia to nitrite and then eventually nitrate. Nitrate is plant fertilizer. Think of a compost pile, when bacteria breaks down organic matter it eventually becomes a nutrient enriched sediment. This is what fuels you plant growth

The plants are rooted into a growing medium which is where all the magic happens. Bacteria makes it’s home on all the surface area provided by the growing medium. When the fish waste water floods the plant bed, the bacteria breaks down the fish waste and leaves the water clean while supplying the plants with essential nutrients for growth. The clean water is then recycled back into the fish tank, and the cycle repeats. Let’s take a look at one of our simple aquaponics systems..

The Ken Aquaponics System

The Ken Aquaponics System with a cutaway


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