Students hooked on aquaponics

Mia Dalzotto, 8, in year 3, and Georgia Sampson, 8, in year 2, inspect some of their handywork in the school's hot house. Picture: KYLIE GOLDSMITH
Mia Dalzotto, 8, in year 3, and Georgia Sampson, 8, in year 2, inspect some of their handywork in the school's hot house. Picture: KYLIE GOLDSMITH

WHEN fishing for a new project, Edi Upper Primary School found something interesting to whet their imaginations — aquaponics.

They’ve installed two 1000-litre tanks and stocked them with rainbow trout, which are part of a complex pump and pipe system that ensure plants in the hothouse get their required nutrients.

The idea was the brainchild of former principal Mick Cross and parent Pete Jewson.

“The idea is the plant matter takes the nutrients from the fish waste, which is all collected in another tank and pumped back into these tanks,” Mr Jewson explained.

While the tanks are full of food the students had a hard time keeping the fish in the tank.

Trout breed in running water and they were attracted to the water as it ran into the tank — throwing themselves at it and leaping to their deaths at the same time.

The children found many dead fish before working it out and installing a shade cloth layer, which allowed the water through, but not the fish to jump out.

“We started off with 44 fish but I think we’re down to about 20,” Mr Jewson said.

Cannibalism of the weaker fish by the stronger fish has also cut numbers in what has proven to be survival of the fittest.

“The fish have probably been in for six months, the system has been running for 12 months but it will take two years to build up a culture so it’s got a supply of nutrient all the time,” Mr Jewson said.

“But as you can see it works.

“This is the first season ... and we still do conventional growing as well.”

The seedlings are grown in soil in trays under the bed with a constant supply of water for both inside and outside growing.

“It’s just a faster way of striking them,” he said.

“When they get planted you’ve got to wash all the dirt off them because there’s no dirt in aquaponics.

“Then the seedlings get planted normally until root structure takes over from the nutrient.”

The aquaponics system uses kiln-dried clay balls as its growing medium.

Ricky Green, 9, in year 3, was one of the students who washed all the clay balls and installed them in the system.

He told Country Mail he likes being out in the garden during the Tuesday lessons but hadn’t been doing too much fishing outside of school because his rod was broken.

He said he understood how the system works and explains it’s all about recycling water.

His favourite thing to eat out of the garden is parsley.

“It’s just yum,” Ricky said.

He’s got a garden at home, but it’s dedicated to ornamentals like roses.

Ricky enjoys being out in the garden so much he hopes to make a career of it.

“I want to be a gardener,” he said.

It’s passion like this and the knowledge the students are learning which prompted Mr Jewson to get involved for his daughter, who attends the school.

His daughter Molly Homewood, is in year 5 at the school and another of his children will start next year.

“I set it all up — I’m a plumber by trade,” he said of the system.

“We investigated a bit and then made up our minds on how all the bits would work and what we wanted because this is a bit different to normal as far as I’ve seen.”

He said all the students knew how it worked.

“The kids do tests on water for things like ammonia and PH levels on a regular basis,” he said.

The aquaponics program ties in nicely with the Stephanie Alexander Kitchen Garden Program in which the school is involved.

“All the kids seem pretty chuffed with it,” Mr Jewson said.