Prof. at Holar University College
Helgi Thorarensen is a professor of aquaculture at the department of Aquaculture and Fish Biology at Holar University College. One of his main research interests is in the effect of water quality on the growth and production performance of aquaculture fish and possibilities for land based aquaculture. He has published several papers and a review on the subject.
Challenges of growing Salmonids in land based aquaculture systems
Currently, there is a growing interest in possibilities of land-based aquaculture of salmonids. With lower discharge of waste and reduced chances of escapes, land based aquaculture systems can have less environmental impact than cage culture. However, lower investment- and production costs will give cage culture a competitive edge over land base systems. Large volumes of water are required for land based aquaculture, although various methods are used to limit water use. The primary water quality parameters, in addition to temperature, are oxygen, carbon dioxide and ammonia. By adding oxygen while removing carbon dioxide and ammonia, the net water requirements for aquaculture can be significantly reduced. However, as water use is decreased, the quality of the rearing water is compromised, resulting in reduced growth of the fish and even mortalities. In this presentation, results of recent research on the effect of water quality on growth and production parameters will be reviewed.