I have commercially raised Arctic Char at various scales of production since the late 1980's. Over that time I have raised the fish in flow through tank systems, ponds, net cages and high level water recirculation systems. These experiences where a learning curve that lead to development a workable system that consistently produced commercial quantities harvested on a weekly basis. The eventual design was based on high scale water recirculation using groundwater and continuously reusing up to 95% of the entire rearing volume. This system incorporated equipment to filter water and manage wastes. Through development and refinement of farm management and quality control plans antibiotic use was not required to control disease. Fish disease was prevented by implementing a strict biosecurity program and using only certified disease free stock.
Available from B&b Freshwater Fish Farm Gunton Manitoba

Overview of Culture Results

• We have grown Char at stocking densities that exceed the normal for rainbow trout or salmon in similar conditions. In a properly designed and operated system this factor can lead to increased production amounts per unit of rearing space. The high density stocking characteristics of the species can allow the production intensification necessary in controlled systems and provide increased economy of scale.

• Char grow considerably faster at lower water temperatures than most other fish species that I have had experience with. This resulted in reduced cost associated with heating water supplies during the winter months. Better growth can be achieved using temperatures that would be less than optimum for other salmonid species. I have had the best results using water temperatures 12-14 C during grow out of table fish, 5-6C during egg incubation and from 7-10C during early rearing.

• I have obtained food conversion ratios (FCR) of 1 to 1 using a system design and feeding plan developed by hands on experience. This FCR reduced the operating cost and return on investment. ( I suggest that beginners use a ration of 1.2-1.0 to represent average conversions for Char under culture conditions for overall planning purposes).

• Our Arctic Char have consumed food over extended light cycles and even fed better during low light levels. I feel that this attribute offers a tremendous bonus. It has allowed us to use a near continuous feeding program and resulted in better conversions, faster growth and less stress during feeding.

• I have found Arctic Char to generally be less aggressive in their behaviour than rainbow trout or salmon. Char are a schooling fish by their nature, oddly (it may seem) they are more aggressive at lower densities. Aggressive behaviour expands energy that can be converted to growth. There less health consequences from incidents of flesh and fin biting or even cannibalism, that is often associated with aggressive behaviour. I have found that Char actually grow faster and in a more uniform manner at higher densities.

• It appears to me that pound for pound, Char in my systems produced less ammonia (from the metabolic process) than some other fish species. Reduction of un-ionized ammonia is a key requirement to successful management of fish culture system. Elevated levels of un-ionized ammonia can be very toxic to fish. Reduced production of ammonia and lower culture temperatures helped make Arctic Char more favourable to water reuse. Generally the higher the culture temperatures are, the greater the amount of ammonia there will be in an un-ionized (free) form.

• Our marketing efforts have shown Arctic Char to be well perceived, and is considered a unique product offering good appeal in seafood dining. Buyers generally feel that farm raised char are consistent in their flesh colour, texture and size. Users of the products are very happy with the year round availability that farmed fish provides.

• Stock survival we eventually experienced for Arctic Char from "fry size to market" is equal to that  encountered for trout or salmon. We have learned some interesting things about Char culture leading us to select a better operational design and fine tune the rearing protocols, thus improving our survival rates.

The above isn't a scientific or research publication. It represents a snapshot version of my results with raising Arctic Char in a commercial aquaculture farm. I plan to write more pages on this subject in the future.

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