The diving season in Bali is all year long. The best conditions for diving are between May and November. The giant sunfish, or by other name Mola Mola, and some other large pelagics are best spotted between June and October. December through March is considered the rainy season, although on most days it doesn't rain. Temperature ranges between 23-30C/73-86F in coastal areas throughout the year. The water temperature usually fluctuates between 24-29C/75-84F. The average water depth around Bali island varies from 5m/16ft to 40m/131ft depending on the site. Currents can be very strong in some areas. The water visibility is very good and ranges from 10m/33ft to 45m/148ft.
What to see
Coral reefs are very healthy. The hard and soft corals are magnificent and mostly untouched, with numerous sea fans and sponges. Mola Mola, manta ray, barracuda, giant trevally, white tip reef shark and black tip reef shark, ornate ghost pipefish, mimic octopus, leaf fish, frogfish, pygmy seahorse, flamboyant cuttlefish, rare nudibranchs and so much more can be observed here by divers. Turtles are also very common around the island.