Three fish farming companies that jointly run the farm were granted a permit in December 2018 for 3,120 tonnes maximum allowed biomass at the site at Husevågøy, Vestland, about 150km north of Bergen.
But in September last year the County Governor of Vestland withdrew a licence for the site after a leisure diver notified authorities of the presence of the coral.
The companies - Troland Lakseoppdrett, Austevoll Melaks and Langøylaks - appealed the decision and the Environment Directorate granted them a temporary permit to continue until a final decision was made.
The companies then set out 450,000 smolts at 200g.
“The coral in question is not an endangered species, it is commonly found on the coast,” Troland chairman Carl-Erik Arnesen said at the time.
“Surveys and calculations we have also made show that this field of cauliflower coral will not be affected by operations at this site.”
The Environment Directorate decided yesterday not to allow the appeal but has allowed the farm to continue until the current crop is harvested.
The farmers will be required to monitor the cauliflower coral deposits in the area, so that the authorities can quickly impose measures or halt operations if necessary.