Home Aquaponics - Sustainable Food Production

As food prices are ever increasing, self-sufficiency in terms of food will help the urban poor save daily costs yet not lack in nutrition.

Aquaponics is a sustainable food production method where traditional aquaculture (fish cultivation) meets hydroponics (growing plants with mineral nutrient solutions). Compared to hydroponics and aeroponics, this method is the most energy and water efficient method to grow vegetables and fruits while also raising fish for human consumption. Aquaponics uses 90% less water than soil-based growing.

Figure 1: Picture depicts an example of an aquaponics farm. (Source: http://www.proaqua.com/aquaponics)

This method mainly relies on the symbiotic relationship between the plant and the fish. The principle of aquaponics is that the effluents accumulated in the water from the fish tank is lead to a hydroponics system where the waste is broken down by nitrogen-fixing bacteria at the root of the plants. It is then absorbed by the plants as vital nutrients. The water which is now filtered and cleansed is repumped to the fish tank and the closed-loop cycle continues.

Figure 2: The cycling of the water from the fish tank to the growing tray.
(Source: http://www.cityscapefarms.com/soillessfarming/)

As this method relies on natural processes, any addition of chemicals will endanger either the plant or the fish. For example, chemical fertilizers, if added, will be toxic to the fish and cause them to die. In this sense, it will require the home owners to practice healthy, organic growing.
(Source: http://www.aquaponic.com.au/aquaponics.htm)

In this system, a balance is required between the number of fishes in the tank, the size of the tank and the amount of plants grown. If a large tank is used with insufficient fishes reared in it, the plants will not receive enough nutrients to grow healthily. If too many fishes are reared, the plants will not be able to filter the water quickly enough and it might be too concentrated with effluent, thus becoming too toxic for the fishes. A good balance will ensure healthy growth of both the plants and the fishes.
(Source: http://aquaponics4you.com/articles/aquaponics-stocking-densities/)



The proposed aquaponics farm will be located next to the kitchen for the convenient retrieval of fresh produce. A variety of vegetables can be planted at the same time  (it doesn't matter since they do not compete for nutrients in this system) to encourage consumption of different types of vegetables which provide different phytonutrients beneficial to the human body.

Figure 3: A variety of plants can be grown at the same time (here, water from the tank flows through the gravel).
(Source: http://pacific.scoop.co.nz/2012/08/new-aquaponics-project-could-be-solution-for-pacific-food-shortage/)