An oceanic ridge that crosses the Nanuku Passage in the northwestern part of the sea connects the two platforms.

[15] The Koro Sea is part of the marine ecoregion of the Fiji Islands, which is included within the Central Indo-Pacific biogeographic region.

[16] In the field of zoogeography, the benthic fauna of the continental shelf and the sandbanks of the islands up to depths of 200 metres (656 ft) also corresponds to the Indo-Pacific biogeographic region within the tropical framework[17] More than 300 species of hard corals, 1,500 of fish, and 7,000 of sea snails are found there.

[6] Passenger ferries provide periodical service from the Koro Sea to Ovalau Island.

[3] Scuba diving and snorkeling are possible in the Koro Sea but are not widely practiced because of the difficulty of safe navigation of its waters.