Issue No. 7 - October/November 2002
Tanks for all the Fish
Aquaculture is a buzzword amongst export enthusiasts and the activity going on under that banner is earning tens of millions of export dollars for South Australia.
We’re familiar with the impressive fish-farming efforts we see in our coastal waters, but those operations are quite hard to control.
Local company Fish Protech has created something far more manageable — an aquaculture ‘kit’ that lets farmers grow marketable quantities of food fish in an area not much larger than a short-course swimming pool.
Fish Protech is the brainchild of engineer Johan Don, formerly an engineering executive for Westinghouse in Europe. Johan designed the system for humanitarian reasons—as a robust subsistence farming method for developing nations.
“The idea really started about 30 years ago when I was working for fish farms overseas as a consultant. I saw so many problems with these fish farms, the use of chemicals, the use of very high energy and also the problems that nobody could really buy a complete fish farm to start a business,” Johan says.
Responding to these problems, Johan designed a system that recycles 98% of its water and uses minimal power. Water isn’t pumped through the system; differences in specific gravity force the water through solid waste filters and sumps and returns clean water to the farm modules.
Aeration units in the module oxygenate the water and drive a bio-filter for clearing ammonia and nitrate. Solid waste is dealt with by an anaerobic digester. There is virtually no effluent runoff. The operation is silent and almost odourless.
Startup cost for a Fish Protech system is about $1.5 million dollars. Operating it requires mains power, access to clean bore water, and outlays for staffing, fish food and for baby fish, called ‘fry’. Procedures are logical and clear-cut. Manufacturing expertise is helpful—aquaculture expertise is not required.
Johan’s meticulous d...