AGRIMARINE TECHNOLOGIES INC .
Toxic blooms Plankton blooms negatively affect fish in three different ways – mechanical irritation , producing toxins and lowering the dissolved oxygen in the water column – leading to high mortality rates of the fish . “ The reason we lost our farms on the west coast of Vancouver Island to begin with was because of plankton ,” Walker observes . “ We could not protect our fish from natural elements and toxic plankton blooms . Every few years we ’ d grow our inventory – it takes 18-24 months to grow inventory – and then along came a plankton bloom that killed everything .
“ We really wanted to find ways around that . Our system as it ’ s designed currently is able to do that . We have the capacity of drawing water from depth to modulate temperature and avoid plankton . This works in both fresh and salt water environments .”
Ahead of the curve As well as avoiding toxic blooms , this system also helps to avoid sea lice . Sea lice are marine ectoparasites ( external parasites ) that feed on the mucus , epidermal tissue and blood of host marine fish . “ It ’ s big news here and we have never had a sea lice issue in our systems , either the pump ashore or the marine systems that we ’ ve had in play . We believe it ’ s because the sea lice live primarily in what ’ s called the phototropic zone , which is the light-enhanced area of the water that goes down 12-15m below the surface . So , by drawing water from 30-40m below the surface , we are able to avoid the majority of sea lice ,” Walker states .
A low energy pumping system , combined with a proprietary deep-water oxygenation system creates an optimised and healthy environment for the fish . When ATI first introduced this technology , many in the aquaculture business were sceptical . “ It wasn ’ t that long ago that most people in the industry felt that we were heading down the wrong path ,” explains Walker . “ When you look
68 December 2017