Credit: Scrap Pile (Flickr)
Credit: Scrap Pile (Flickr)
February 19, 2014 Aquaponics 1 Comment

Welcome to the essentials of Aquaponics, welcome to Aquaponics 101!

Why should we attempt to spread aquaponics in India?

– In India, a farmer commits suicide every 30 minutes.
– Volatile weather conditions frequently ruin crop that a farmer has worked hard to achieve – meaning he not only has no profit, but is pushed into greater poverty
– Water and land are 2 precious resources needed for traditional agriculture – we don’t have enough of it

Credit: Scrap Pile (Flickr)

Credit: Scrap Pile (Flickr)

Why is aquaponics the solution?

Aquaponics farming uses approximately 2% of the water that conventional farming uses, and a greater crop can be yielded in a fraction of the land. Crops also grow at a much faster rate.

The emphasis is on the vegetables grown – this is the ‘cash crop’ so to speak, and the fish are the ‘fertilizer factories,’ although the fish can also be sold for food for additional income.

What exactly is it?

A combination of fish farming and hydroponics = aquaponics.

Hydroponics is the cultivation of plants without soil – using only water. The problem with this method is that in order to deliver the correct nutrients to the plants, artificial (and often costly) formula’s need to be added to the water.

However when we introduce fish, and use the ecofriendly ‘circulating aquaculture system,’ the waste from the fish tanks feeds the plants, providing them with all the nutrients they need. The plants then clean the water ready to go back to the fish.

So how exactly does it work?

The process starts with the fish. (many types of fish can be used – catfish, trout and tilapia being common choices) and a variety of breeds can be used together in one tank.

Credit: Kanu Hawaii (Flickr)

Credit: Kanu Hawaii (Flickr)

Once the fish are fed and release their waste, this then gets pumped to an intermediary tank – a ‘clarifier or settler’. This is where the mineralization of the waste takes place. This breaks down and releases nutrients to the water.

The water then moves to a biofilter which allows for ‘nitrification’ – a natural biological process. Amonia is released into the water – the natural bacteria present uses oxygen in an aerobic process that converts the ammonia to nitrite – then to nitrate.

This nutrient rich water is now ready to move to the plant beds.

There are numerous ways to organize the plants in the tanks. Perhaps the most common sees the plant balanced on Styrofoam rafts with the roots placed through a hole and immersed in the water. They soak up the nutrients they need, as well as filtering out the nitrogenous compounds that are toxic to the fish. The water then pumped back to the fish tanks.

The water is constantly recycled so the process is highly water conservative and green-friendly.

Things to remember

Access to water and a reliable electricity/energy source is required. This is needed to keep the fish tanks at the ideal temperature and run pumps to circulate water between plants. However, even if power is lost for a few hours, it is unlikely there will be any significant problems. There is far less maintenance and manual labor needed as compared to traditional farming, but regular observation is required, such as checking the PH balance of the water.

The many benefits

– This method 100% organic (if it wasn’t organic, the fish would die). This means we can guarantee we are creating organic vegetables and fish.
– We get two crops in one process – vegetables and fish
– The plants grow quicker than in traditional farming, allowing for greater turnover. For example, a lettuce can be grown to full size in about a month (3 months when grown traditionally).
– Farmers are able to grow exotic plants that may not be native to the region – meaning the product is ‘exclusive’ and farmers can charge more from buyers
– The controlled environment means the plants are less susceptible to disease and damaging weather elements, it also means a farmer benefits from a consistent crop all throughout the year
– All crops and varieties can be cultivated year round – not just seasonally.
– Fish do not carry pathogens such as E-Coli and salmonella that warm-blooded animals do
– Unlimited potential to grow high quality food from almost anywhere
– Plants can be spaced close together, meaning more plants (and therefore profit) can be grown
– It is a closed system so there is no evaporation, and the water doesn’t seep into the ground so there is little wastage. Therefore a farmer does not need to rely on rainfall.

Indeed, the only downside is the initial cost required to set up the system – however the profit potential should soon cover this.

Did you know?

Aquaponics is not new, but for some reason it has been long overlooked and forgotten.

The ancient Aztecs used a system of aquaponics with stationary floating islands called Chinampas where they manually collected waste from the fish in nearby canals to feed to plants.

Ancient Egyptians and Chinese are thought to have used aquaponics systems too, as well as the Hanging Gardens of Babylon, all of which used a system of growing plants without soil, above fish.

We could be in worse company, hey?

Class dismissed!

Pippa Woodhead
Written by Pippa Woodhead
Being a health-nut, London born Pippa has struggled to adjust to the lack of availability of lettuce and kale since re-locating to India. Previously naive to the extent of the worlds food struggles, she has now become obsessed with sustainability in food production and especially in India where it needs it the most (plus she’s also hoping to get her hands on some kale any day now). When she’s not writing for Aquaponics in India, she is usually found with her head in a book or in the kitchen experimenting with new vegetarian recipes.