An aquaponics raft in the fish pond?
Yes you can transform a fish pond into a nice aquaponics system with this simple technique!
All you need is a foam raft and semi aquatic plants.
Many aquaponics enthusiast would like to experiment DWC also known as Raft systems. However, this technique requires a special tank dedicated to the plants. The DWC tank is separate to the fish tank and therefore requires space.
But, there is a solution to grow plants on raft directly in the fish pond. This technique is doable both on an existing aquaponics system or on a simple fish pond.
Some advantages of having a raft on your fish pond:
Aquaponics raft produce more plants
If you are starting with a simple fish pond, this technique will allow you to produce plants. Plants are very aesthetic but they can also be part of your diet! If you already have an aquaponics system, this technique offers more plants real estate.
Floating raft consume nitrogen (nitrate)
Adding a raft with fast growing plants will consume a lot of nitrogen (especially nitrate). which will allow you to stock more fish in better condition.
Rafts limit algae development
The raft is also covering the surface of the water. Hence, it will decrease algae development and offer a nice shelter for your fish. Your aquatic friend will love swimming among the roots. Some fish species such as goldfish will actually use the roots as a spawning support.
What type of aquaponics raft?
I usually like to work with natural material. Hence I started the experiment with wood sticks. Unfortunately, the floatability of the raft was not great. Hence, I opted for a more reliable solution and recycled an old bodyboard. I drilled a few little holes inside where I could simply slide plant cuttings inside. I also made larger holes where I added pots filled with scoria. Both technique a working very well. You may be able to recycle other type of material. The main factors are: It must be food grade and offer a good floatability.
What type of plants?
This type of float is different to a DWC. Here the water is not really purified and the oxygen supply is limited. Hence, only semi aquatic plants will strive in this environment. I would highly recommend growing plants such as watercress and mint. Not only they are fast growing but they are also very tasty!
Aquaponics raft and oxygen concentration!
When you add a raft full of plants on your fish pond, the plants will breath trough the roots. Hence, the oxygen level may decrease in your fish tank. Hence, keep an eye your oxygen level or fish behavior in the morning before the sun raise.
Give yourself a treat and install an aquaponics raft on your fish pond!
Feel free to send me your pictures/video, I would love to hear about it.