QUESTION: What do you get when you cross hydroponics with aquaculture?
The system works by using water from aquaculture to irrigate hydroponically-grown plants.
Aquaculture water quickly becomes nutrient rich and these nutrients are normally removed through expensive treatment methods.
Aquaponic systems work by using nutrient wastes from aquaculture to feed plants which are grown hydroponically.
Water from aquaculture ponds is pumped into ‘flood and drain' trays on which the plants sit.
The plants soak up waste nutrients from the pond water, after which the water is returned to the fish tank.
According to SCU student Jed Tissott, the closed system is gaining in popularity in Australia and there are already a couple of small systems operating on the Northern Rivers
It also had the potential to be used in large-scale commercial aquaculture, he said.
Mr Tissott said the system should be attractive to freshwater aquaculture industries because of the water savings it promised.
Another exhibit in the Sustainable Living Expo is the Northern Landcare Support Services information stand, where you will find a pamphlet on a free upcoming biodiversity field day at Lillifield Community, Wadeville. For further more information phone 6632 3722.
North Coast Weeds also has an information booth at the expo. Landholders are invited to drop by and pick up aninformation sheet on hymenachne, for which Industry and Investment NSW has released a weed alert. Hymenachne is a semi-aquatic grass which is becoming a major weed in wetlands.
A pamphlet to assist landholders to identifyalligator weed can be also picked up from the stand.
The Permaculture College of Australia is also at the expo with information on all of its permaculture design courses, run at the college's campus at Djanbung Gardens, Nimbin.
A summer school intensive course will run from January 7 to 21. A part-time course will run from February until April and a winter school intensive will start next July.
Also on at the show is the Northern Rivers Regional Food Celebration, featuring exhibits from local food producers, cooking demonstrations, wine and coffee tasting, and a macadamia nut-cracking competition.
Australia's top rodeo riders will take centre stage in the rodeo ring from 1pm to 6pm today and tomorrow.
The North Coast National is currently on at the Lismore Showground and ends on Saturday.