How to build an Aquaponics System
If you’ve ever wondered how to build your dream aquaponics system, the internet has brought you to the right page. Aquaponics is an age-old fish rearing and plant growing sustainable system, refined for the modern age with the advancement of technology. With the fusion of two distinct but complementary systems – hydroponics, i.e., simply growing plants in water, instead of soil; with aquaculture, which is the farming of fish, brings us aquaponics.
This merging together of two natural and self-sustaining mechanisms in a syncretic and symbiotic bond, is the need of the present and the future. The science of aquaponic gardening lies in our ability to understand that the waste generated by fish acts as nutrition for the plants, who in turn clean the water for the fish in an unending cycle. Bacteria act as a medium, who break down the complex fish food. The rearing of fish in open tanks (without plants) exposes them to the same regurgitated and ammonia rich water, needing them to be injected with heavy antibiotics, unlike aquaponic fish.
The Components of Your Aquaponics System
All aquaponics systems have certain common components, that are tied together by the science of recirculating water. The aim of anyone who plans to setup a DIY aquaponics system is to mimic this ecosystem, by creating a separate space for both the aquaculture and the hydroponics, and then connecting them.
These are the following common parts of every aquaponics system –
The Fish Tank
Where the fish are raised, fed and reared. This can generally be in the form of an old aquarium lying around at home.
The plant tank/container
This is where the hydroponics subsystem is carried out and the plants are grown. Depending on the kind of system, the plant tank can either be a PVC pipes, yet another fish tank or container, or perhaps a grow bed with media (like gravel or perlite) in it.
To take water from the fish tank to the hydroponics subsystem. Generally, it’s tubed with filtration parts in such a way, that the water is carried back after nutrification, to the fish tank.
Appropriate to the scale of the fish tank, to keep the bubbling and oxygenation of water constant.
It is a separate space that allows bacteria to grow and colonize. Though not essential for every kind of set-up (compulsory for NFT system), bio-filters help with pH control, dissolved oxygen and temperature control. It is a space where the ammonia can be converted into usable forms for the fish, by the bacteria.
To keep the fish tanks bubbling, oxygen flowing and the ecosystem alive, a power backup is a must that is separate from the original power source.
The Dream Aquaponics System: What Should You Choose?
It is often said that with an aquaponics system, setting up is the hard part. Once a set-up is in place, very little maintenance is required. Roughly, there are four broad designs, within which certain clever changes can be made depending on the material that you can access. There is, of course, the very basic question of choosing your aquaponics fish and the appropriate aquaponics plants, for which our previous blog will suffice.
In the meanwhile, let’s look at the three broad methods and designs of setting up an aquaponics system:
The Raft System
Very simply – rafts on water! Also known as float, this system involves a polystyrene board, which floats on water, on which plants are grown, and their roots are allowed to seep deep into the water. Even in a small, DIY raft-system, the raft tank hosting the foam board, will be separate from the fish tank, connected to each other via filtration components. The raft tank acts as a water buffer for the fish, protecting them from the stress of ammonification, while also giving room to the extra bacteria to flourish. This system can also be implemented on a large scale, in greenhouses for example, where the size and scale of implements is altered to fit the setting.
NFT (or Nutrient Film Technique)
Flexible again with scale of operations, plants are grown in long thin PVC or gutter pipes, which are exposes to periodic bouts of nutrient rich water. Water flows from the fish tanks and back through similar filtration components, with the addition of a bio-filter required, for the storage of excess water and the bacteria in it. NFT is the most conducive for growing those leafy aquaponics greens. By most estimates, this is not the easiest DIY home aquaponics system that you can create, but for the more ambitious readers, certainly possible.
In this, a bed filled with media like gravel or perlite is placed in a tank or container. Water is pumped through filtration components, from the fish tank, at periodic intervals, and then drained back. The waste and excreta of the fish is broken down within the plant beds, in a slow process where sometimes agents like worms are used, to quicken the pace. While this is not the most seasoned method for those seeking commercial cropping, this is the easiest, and most effective DIY aquaponics system, especially for novices just starting out.
If you’re deprived of space or stay in a tiny apartment, but are hugely committed to having your own aquaponics garden, the vertical system is the way to do it. Using PVC pipes placed vertically above the fish tank, one can create many different levels of vertically stacked plants. The water will glide down the pipes, in controlled quantities, providing nutrition to the plants, and then flow over to the fish tank. This system, too, will be needing a biofilter.
pH in your Aquaponics System
pH or the ‘Potential of Hydrogen’ is a scale used to determine the acidity or basicity of a given aqueous solution. Measured on a scale of 0 to 14, with 7 being the neutral value, acidity has a substantial influence on the absorbability and solubility of a number of food elements. In addition, it leads to the breaking down of organic substances, influencing the structure, composition and nature of micro-life in the solution.
For any grower, the biggest challenge is always keeping the pH level in the optimum range. One is not just responsible towards the sensitivity of aquaponic plants, which will die in too acidic or basic a solution, but also the aquaponics fish, that cannot survive heavy fluctuations. There is also to consider the bacteria themselves. With these three living organisms in mind, a generally neutral pH range of 6.8-7.2 is ideal.
Final Thoughts on Your Aquaponic System
A combination of the science, with a clever use of implements and a well-installed filtration system, will ensure that you have a healthy, vibrant and flourishing ecosystem in your aquaponics set-up. An important thing to keep in mind is that aquaponics provides a departure from traditional agriculture, which means that dependency on pesticides and insecticides and other chemicals is a thing of the past. We should not settle for anything but the freshest and cleanest produce, that will take care of all our dietary requirements, in an organic manner.
Like any form of nurturing, the aquaponics system requires constant monitoring to check for excess waste, fluctuating pH levels and access to oxygen. Pick plants that are compatible with fish in this setup and these conditions, to ensure the smooth functioning of the recirculating system. The aquaponicsfish that thrive with almost any produce, are freshwater fish like tilapia and barramundi. The best part is that you can grow all your meals through your aquaponics garden!