What is aquaponics? - Guest post with Jonathan Martinetto

Have you ever thought of aquaponics as an option for your food production?  Have you even heard of aquaponics?

This is a guest post from Jonathan Martinetto, the founder of Melbourne Aquaponics. His digital aquaponics manual, “The Art of Aquaponics”, is considered as the aquaponics bible!  You may remember that Pete and I bought an aquaponics kit several years ago, but didn't set it up at the time because we planned to move, so we are always keen to learn more about this unique method of growing food.

Producing our own food is becoming more and more important. We can’t trust the food from the supermarket anymore... Permaculture is a perfect way to produce healthy food locally with a very limited impact on the environment. Aquaponics is one branch of permaculture allowing you to produce both fish and vegetables in your backyard!

A bit of history of aquaponics

Aquaponics is very much in trend but sometimes misunderstood. Indeed it is too often mixed up with hydroponics which is a modern technique used to produce vegetables without soil. As opposed to hydroponics, aquaponics is a very old technique known for thousands of years and used in Asia to grow fish in the rice culture (Paddy field).

How did it work? I am glad you ask!

The fish were eating the pest (insects) that were growing on the rice. The rice without pest was therefore growing in better condition. The fish were also releasing nitrogen into the water which was a source of nutrients used by the rice. By using this nitrogen, the rice was purifying the water, keeping a suitable environment for the fish. When the farmer harvested the crop they could enjoy a huge rice production plus an extra fish crop highly appreciated.

Looking at this principle we can see that by switching from a mono-culture system (only one species grown) to a poly-culture ecosystem, the “pest” management is self-regulated (no need of pesticides needed thanks to the fish) and the rice nutrients are free (no need of external fertilizer). It seems magical but this cycle happens in all ecosystems around us (forest, lake, river…) and is called “The cycle of life” or “The nitrogen cycle”.

A world of possibilities for aquaponics…

Now that we have defined the aquaponics principle, it is interesting to know what type of production we can grow in aquaponics. First it is important to understand that while most of the aquaponics communications are often focused on the fish, the real productivity of the ecosystem will result in plants and vegetables. An aquaponics system generally produces 10 times more vegetables than fish. It actually makes sense as vegetables are primary organism. Fish take more time to grow.

The type of vegetable you are able to grow in aquaponics will be dependent on the area where it is applied. Each species has specific temperature requirements and we will not be able to grow the same species in tropical conditions or cold conditions. There are many possibilities and nearly anything that you can grow in soil you can also grow in an aquaponics system.

What fish can you grow in aquaponics?

If you live in Europe you will probably be able to grow rainbow trouts which is a fantastic eating fish.

If you leave in a tropical area, tilapia and barramundi are more appropriate options. Talk to your closest fish farm to see what species they are growing. Obviously we are growing freshwater fish only. If you begin you may want to focus on hardy fish such as goldfish who will more likely survive through your first mistakes…

What vegetables can you grown in aquaponics?

Most plants are able to be grown in aquaponics. Keep in mind though that we are offering a moist environment so stay away from cactus and succulents. When you begin at aquaponics you want to start with leafy vegetables such as lettuce, spinach, cabbage... Once the ecosystem is fully developed (after 6 months to one year) you can grow more varieties including fruits such as strawberries, tomatoes, chilli...

Aquaponics in your backyard!

How do we apply this specific technique in the backyard? Let nature do the work for you!

There are different types of aquaponics systems such as: the raft system; the vertical aquaponics and the flood and drain growbed technique. The latter is the most adapted technique for backyard aquaponics and only requires 2 tanks (a fish tank and a growbed sitting on top). A little water pump is necessary to allow an appropriate water movement. More technical information is provided in the 6 STEP guide available at the end of this article.

The main advantages of Aquaponics

• In an aquaponics system the water is recycled. As a result it consumes 10 times less water than a classic garden!

• The plants have constant access to the nutrients and moisture of the system. Unlike a classic garden there is no need to spend time watering or working the soil. Plants are growing twice as fast as in a classic garden.

• The growbed is raised so very few to no weeds are colonizing. You don’t spend time weeding the growbed.

• The production is 100% natural, no pesticides are used.

• The system can operate in a very limited surface area (as small as one square meter).

• It helps people reconnecting with nature, bring nature in your backyard (insects, worms, birds, butterfly…).

• It is a real feature in your backyard and can have a double purpose (bench, table…).

Less chore, more pleasure…

The aquaponics system actually is very low maintenance. The most regular tasks are feeding the fish and topping up the water level when needed. At the beginning you will like to test your water to ensure everything is ok. With practice you will probably test your water less and less often.

The next step!

If you are interested in starting or learning more about aquaponics you will probably be interested to discover the six steps to build and manage an Aquaponics system.

Have you tried aquaponics?  What do you think?