Aquaponics is a method of growing plants and raising fish and other water creatures in a mutually beneficial way.
Aquaponics, along with hydroponics, is a type of aqua gardening. Indeed, aquaponics is so closely related to hydroponics that it is known as organic hydroponics or hydroponics with fish. Aqua and hydro both mean water, so it shouldn’t be a surprise to learn that with both of these forms of cultivation water is the big focus rather than soil.
The word aquaponics comes from combining the names of 2 different methods of cultivating plants and water organisms.
As I said above, aqua means water. Aquaculture, also sometimes called aquafarming, relates to breeding and raising creatures that live in water. This includes a wide range of organisms, from fish like salmon and trout through to crustaceans like prawns and molluscs like oysters. It can even refer to growing seaweeds and types of algae.
The ‘ponic’ part of the word comes from hydroponics. This is a method of growing plants without soil. Put simply, plants are given a nutrient-rich solution which supplies them with everything that they would get from a healthy patch of ground. At its most extreme, this means plant tops sticking up through plastic tubes whilst their roots dangle in water super-charged with nutrients.
For a more detailed explanation of the wonders of hydroponics, please have a read of our explainer article.
How Does Aquaponics Work?
It’s a brilliantly straight forward system.
Like all other creatures, aquatic animals, whether they are salmon or oysters, produce some form of waste. In aquaponics, this waste is used to feed plants. However, that isn’t all as the plants clean the water that the fish etc live in. It’s a clever combination of 2 methods of farming which appear at first glance to be unrelated.
Of course, it is all a little more complicated than that.
Firstly, aquaponics relies on a closed-system, where the water recycles from fish to plants with nothing interfering or escaping.
Secondly, much of the success of an aquaponic system depends on having the right bacteria doing their magic and helping the process of fish waste to plant food to move along.
The waste products from the fish, molluscs and algae living in the water have varying levels of ammonia and bacteria is needed to break it down and turn the ammonia into nitrates. Many of these bacteria lurk amongst the roots of the plants hanging in the water and they turn the fish waste into a nutrient-rich solution that the plants happily absorb, just as they would in a regular hydroponic set up.
Even better, not only do the plants thrive but the aquatic organisms do too. If you were one of those kids who came from a fun fair with a limp-looking goldfish in a murky bag of water you’ll know that even one pet fish needs its water changed and bowl cleaned on a regular basis. Unless you have a decent filtration system, any kind of aquarium has to be cleaned periodically or all the waste, solid and otherwise, from the fish and so on builds up in the water and it eventually becomes toxic. So toxic, that poor little goldfish may end up floating lifeless on the surface of its tank, if you leave it for too long.
With aquaponics, as long as you have the right plants and ammonia-loving, nitrate-producing bacteria, the waste doesn’t collect but is instead converted into plant food.
If you’d like to know about how aquaponics is being used in commercial farming, you can read more here.
There are so many reasons to choose aquaponics as a method to grow crops and I go into some of them in more detail in another article.
For now though, let me highlight a few of the most important. It’s an extremely efficient and productive form of farming.
It’s also totally organic and replicates a natural ecosystem. So if you want to get away from human intervention, stop using man made nutrient solutions to feed your lettuces and at the same time reduce the waste produced by your cultivation, it’s hard to ignore the wonders of aquaponics.
There’s also the fact that once you’ve set your aquaponic system, it’s incredibly cheap to run as you aren’t constantly topping up nutrients or flushing out and replacing water.
Plus, if you choose your plants carefully and do a bit of homework on the fish and crustaceans that you pop in your aquaponic setup, you can score the double win of growing veggies and delicious fish all from one growing environment. A fresh, fish dinner with a side of organic salad, all from the same tank? Who wouldn’t want that?
It’s easy to see why so many home gardeners and commercial producers see aquaponics as the future for both small and large scale farming.