GREEN LINE:  Waikiki Aquarium offers a look into the spectacular tropical waters that surround Hawaii. While it is small compared to many modern facilities, many of the exhibits are unique to Waikiki. The indoor area offers four galleries, starring nautiluses, reef sharks, flashlight fish, lionfish, piranhas, and a wide variety of tropical fishes and corals. Outside visitors can see the 75,000 gallon Edge of Reef habitat, Moi hatchery and the endangered Monk seal pool. Waikiki has pioneered efforts to farm corals, which visitors can see at the coral farm. Aquariums from around the world request live corals from Waikiki.