Sumbawa Island is located east of Lombok Island and west of Komodo Island in the Nusa Tenggara. Sumbawa and the surrounding islands of Sangeang, Sumba, Madang, Moyo and Satonda has some excellent diving and often form part of a Komodo liveaboard itinerary for boats departing from Bali. Marine life is prolific and underwater visibility is excellent. Above water the volcanic scenery is impressive including a sacred lake and a huge colony of fruit bats at Satonta that take flight at dusk. Sumbawa can be dived all year round.
Moyo Island off the north coast of Sumbawa is less dived these days since corrupt village chiefs like to extort bribes from liveaboards in the name of conservation. However the effects of dynamite fishing are clearly evident. Angels Reef is a deep wall with good marine life, healthy soft corals and gorgonian seafans and the chance to see blacktip reef sharks at depth. Currents can be strong. At Panjang Reef it's possible to find the highly toxic blue ringed octopus.
The Car Park in northern Sumbawa is full of giant moray eels.
Gili Madang has some interesting dive sites including a wall dive to the southwest with plenty of sharks.
Tanjung Batu Putih is a sloping reef to 20m then a drop off down to 40m. It is home to two endemic species of angel fish, the blue and gold bi-colour angelfish and the Lamarck's angelfish. Eagle rays and reef sharks are seen on the drop off.
Satonda Island has fairy average coral coverage but is excellent for critter diving. The rare and difficult to spot clown frogfish can be seen here. Ornate ghost pipefish, seahorse, leaf scorpionfish and lionfish can also be seen here. Night dives are also rewarding for macro photographers when all manner of crustaceans can be seen including boxer crabs and hermit crabs. Currents are normally mild.
Sangeang Island, a still active volcano island, has healthy hard and soft coral reefs in clear water. Mentjeng Wall is great for critters like nudibranchs, cowries, ribbon eels and crustaceans. Maximum depth is 25m, currents can be strong. Copycat Copycat is named for the mimic octopus that are found here. Black Magic is named for the black volcanic sand and is another good macro dive site. Bubbles can sometimes be seen escaping from air vents the seabed here.