HAWAI‘I OFFSHORE AQUACULTURE RESEARCH PROJECT

Features of HOARP:

• The SeaStation 3000™, a bi-conical sea cage, is submerged 40 feet from the surface, out of the high energy zone, to reduce the risk of harm to the cage or the fish in the event of very large ocean swells.
• The cage is 2,600 cubic meters or 24 meters in diameter and 15 meters in depth (about 80x50 feet).
• The cage is anchored in 100-feet deep waters, and does not affect boats and ship traffic.
• The cage is stocked with over 70,000 Pacific threadfin, or moi, as they are known in Hawai‘i.
• The moi are fed commercial fish pellets that provide a rich diet for optimal growth. They are fed twice daily through a pipe into the cage, operated from a boat at the surface.
• Uneaten food and fecal matter blow out of the cage and strong ocean currents quickly dissipate waste matter. This is an advantage of an open ocean system as compared to near-shore net pens. In addition, fish congregating near the cage will consume any extra feed that falls through the net.
• Two divers scrub the cage daily to ensure that water continues to flow through the mesh.
• After four months in the cage, the fish will begin to be harvested, with harvesting continuing for the next few months. At market size the fish are 3/4-pound to one-pound.
• The cage is made of a steel core, with cement ballast at the bottom, and a framework of steel pipes connected by a strong synthetic mesh that divers can enter. The net material, Spectra has the strength of steel and was developed by NASA. This lightweight material is manufactured by Net Systems of Bainbridge, Washington.