Let’s talk about the different type of aquaponics system options
It’s a question very often asked and very tricky to respond. It’s like asking “what is the best car?”. Indeed, we all have different responses to those questions. In fact, it depends on your preferences and your needs. Will you drive in the city or in the country side? Are you the only passenger or have you got kids? In this article we will review the different type of aquaponics system options and their specificities.
When it comes to aquaponics systems, there are 3 big categories (and a multitude of hybrid subcategories).
Flood and Drain Backyard Aquaponics
This system is probably the most commonly found in backyard aquaponics. Basically, it consists of a fish tank and a growbed (full of media). Also, the growbed is equipped with a bell siphon allowing the water to flood and drop back in the fish tank all at once.
Advantages
The media into the growbed is porous and offers a huge surface for the bacteria to leave on. So even if the plants die, the bacteria present on the media will transform the toxic ammonia into nitrite and then nitrate.
As a Result, it is well adapted to small scale backyard aquaponics. Furthermore, it doesn’t require a large surface and is relatively easy to balance.
Cons
However, this system requires to clean the growbed when clogged (every few years).
Deep Water Culture (DWC)
The Deep Water Culture system is composed of a fish tank and a culture tank of at least 30cm deep (often deeper). The culture tank is equipped with air stones or air pipes. On the water surface we have floating rafts made from polystyrene. Then, the rafts are equipped with holes. Pots are placed in the holes and the plants roots have access to the nutritive water just underneath. The air stones allow a nice oxygenation of the plant roots. The plant roots offer a large surface area for bacteria.
Pros
This system offers an easy harvest and planting. It is well adapted to large scale aquaponics.
Cons
Require a large surface. The bacteria are mainly present on the plant roots. If the plants die, we lose the bacteria population. Robust systems involve a separate biological filtration which adds complexity and cost into the system
Nutrient Film Technique (NFT)
The nutrient film technique is composed of pipes with holes on the top. The principle is to let some water from the fish tank running into the bottom of the pipe. Some plants in pots are placed in the pipes holes. The plants roots are reaching film of water and able to absorb the nutritive substances.
Pros
Those systems can produce a significative quantity of food per surface. They can be placed on several layers horizontally if enough light reach the plants canopy.
Cons
The bacteria are mainly fixed on the plant roots. If the roots die, the bacteria disappear leaving the system with toxic nitrogen molecules (ammonia and nitrite).
Conclusion on the type of aquaponics system
The outcome of this overview is that there is no one best type of aquaponics system. Depending on your level of experience and surface available you will choose a different option. If you are starting aquaponics I recommend you the flood and drain grow bed aquaponics.
you will probably be interested to discover Jonathan’s six steps to build and manage an Aquaponics system. Click here to access for free! Thanks and good reading 🙂