Open Blue Cobia/Black King Fish (Rachycentron canadum)

Open Blue, founded by Brian O’Hanlon, is a pioneering company dedicated to developing open ocean sustainable fish farming technology. Fish are raised from egg to adult in 1-2 years in the southern Caribbean Sea.

This is an exciting new venture producing an exceptionally high quality fish new to the UK. Cobia or Black King Fish is already successful in US and Japan and is appreciated for sashimi grade quality. Cobia are sustainably produced alternatives to premium fish such as Chilean Seabass, Sablefish, Yellowtail and White Tuna.

Open Blue have the largest deep water farm in the world which has neutral environmental impact. The fish are grown 12 km offshore at 100meters + depth in a low intensity closed net system, which has 97.5% water to 2.5% fish biomass ensuring clean, healthy, Cobia fish. Open ocean currents of 1.5 – 2 knots provides clean water which is free from parasites & ensures muscular flesh development in the fish. No pesticides are used.


They are harvested by slowly raising the deep water cages to the surface. Fish are sucked out gently in flowing water into a well boat (which carries water tanks). They are taken to a holding tank where they rest and are fasted to clear the guts.

Killed humanely when in a calm state by electrostunning, they are bled and gutted immediately. This way of handling minimises stress, which delays the onset and depth of rigor mortis and results, just like meat, in a more tender, cleaner and tastier product.

They are immediately put into ice slurry chilled to 0 to 1 deg C, and then held on ice. This slows the growth of bacteria causing spoilage and delays the natural enzymatic breakdown of the flesh. Microbiology and taste test results by independent parties have shown that if kept correctly in ice, bacterial counts do not start to climb until 18 days after harvest.

Supplied directly toFundamentally Fish who have full traceability and are EU registered for fishery products. There are no wholesalers involved in the chain.

Open Blue Cobia was Aquaculture Stewardship Council accredited in 2014 (new standards had to be written for Cobia raised in this way). Global Gap quality standards are in place for processing.

Copy & click this link to go to the National Geographic article about Open Blue in June 2014 or check out their website at