02 AM | 15 May

Aquaponics Turns Fish Waste to Fertilizer in Wairakei Primary School


When Wairakei Primary School closed down its pool, no one would have thought that they could make a sustainable garden out of using fish. The New Zealand school announced the official opening of their won aquaponics unit this week, which turns waste produced by farm-grown fish into fertilizer.

Sustainable gardens

Diana Fitzsimmons, the school’s enviroschool leader along with representative Amandao Jones worked together and raised $13,000 to create the unit, which is now housed where in the school’s old pool. Jones notes how supportive the community was for their project, noting that many people gave time and donated goods to help make the school’s first aquaponics a success.

AquaponicsAquaponics is a more organic and sustainable form of cultivation which involves using plants and animals such as fish within a water tank. Instead of pitting mixes, water is used and is essentially a ‘soilless’ form of gardening. Jones said that she was ‘excited that people are able to see the fish because no one really knows what aquaponics is, so it’s a little confusing and what makes it so super cool and exciting is the fish.’

The system relies only on the natural ecosystem the fish and the plants create within the water tank, with the only thing needing replacement is water that has already been absorbed by the plants or evaporated in the air. The fish’s role is to provide the nutrients that plants need via their waste, and they in turn depend on the plants for oxygen. Since the plants are in the water, herbicide is also not necessary.

The school planted the first vegetables almost five weeks ago, and some are looking ready to harvest. They note that the process is speeding up the longer the aquaponic unit runs, and they are expecting their lettuces to mature in as little as twenty-one days.

An educational process

The students will be learning more about the aquaponics unit and how it works, such as feeding and looking after the fish and caring for the crops. Fitzsimmons notes that the students will be the ones feeding the fish, as well as doing water testing to see and checking if the water is viable. Jones hopes that the success of their aquaponics unit will grow in popularity in other schools and areas that are looking to decommission their pools, which she notes as becoming ‘very common.’

Supporters of aquaponics notes that this new method is perfect for people looking to grow consistent crops without having to invest on too big of a space for planting.