Hawaiian Trough the Hawaiian Arch. The Hawaiian Arch extends about 200 meters above the surrounding ocean floor, and contains tilted coral reefs. The coral reefs in the Hawaiian Tough are described as mesophotic coral ecosystems, which can be found between 100 and 500 feet below sea level. 43 percent of fish species documented at the mesophotic reefs are unique to the Hawaiian Islands. At Maui’s ‘Au’au channel the largest uninterrupted mesophotic coral ecosystem was discovered, with an area larger than 3 square miles. These reefs contained many stony, reef building coral that belong to the genus Leptoseris, which are adapted for deep
Channels of the Hawaiian Islands Molokaʻi Channel) separates the islands of Oʻahu and Molokaʻi, and is wide. Maximum depth is . There are annual paddleboarding and outrigger canoe paddling contests which traverse this channel. Ka Iwi means "the bone." The Kaʻieʻie Waho Channel separates the islands of Kauaʻi and Oʻahu, at a distance of . Kaʻieʻie Waho means "Outer Kaʻieʻie," named after the ʻieʻie vine ("Freycinetia arborea"). The maximum depth of the channel is over 11000 feet. The Kaulakahi Channel separates the islands of Niʻihau and Kauaʻi. It is wide. Kaulakahi translates to "the single flame (streak of color)." The Kumukahi Channel separates the islands