Koh Tachai Reef is a marine site featuring a combination of reef, pinnacle, and drop-off topography. Located 70 kilometres from shore, this site requires boat access and is suited for intermediate divers due to the presence of strong currents. Depths range from 5 to 40 metres, with an average depth of 25 metres. Visibility varies between 10 and 40 metres, and water temperatures remain warm throughout the year, typically between 28 and 31 degrees Celsius. Divers should be aware of hazards including deep water, strong currents, and sharp coral. Night diving is permitted at this location, with typical dives lasting 60 minutes.

The Aquarium at Koh Tachai is a reef site offering depths between 3 and 14 metres, with an average depth of 8 metres. Suitable for beginners, the site features moderate currents and visibility ranging from 15 to 30 metres. Divers and snorkellers may encounter uncommon species including Day Octopus, Titan Triggerfish, Giant Moray, Harlequin Sweetlips, Spotfin Lionfish, Pink Skunk Anemonefish, Groupers, Painted Spiny Lobster, Brown Butterflyfish, Blue Dragon, Redtooth Triggerfish, Powder-blue Surgeonfish, Wrasses, and Bluefin Trevally. Entry is possible via boat or from the shore. Water temperatures typically remain between 28 and 31C, though rare thermoclines can lower this to 27C. Hazards include sharks, sharp coral, and strong currents. Showers are available on-site.

Turtle Rock is a reef site located off Koh Tachai, Thailand, accessible only by boat. The site features a depth range of 5 to 30 metres, with an average depth of 12 metres. Divers and snorkellers can expect mild currents and visibility ranging from 10 to 30 metres. Water temperatures remain consistent throughout the year, typically between 27 and 30 degrees Celsius. The site is suitable for beginners and supports night diving, with typical dives lasting around 45 minutes. Due to the nature of the location, boat traffic is a noted hazard for divers and snorkellers to monitor during their time in the water.

Ko Bon Pinnacle is a challenging deep-water site located 200 metres off Koh Bon. This submerged pinnacle features a wall and drop-off topography, with depths ranging from 18 to 39 metres. Due to strong currents and potential down currents, this site is strictly for advanced divers. Visibility varies between 10 and 30 metres, and divers may encounter cold water gusts and plankton blooms. Marine life frequently recorded here includes giant moray, coral grouper, titan triggerfish, moorish idol, and various groupers. Rarer sightings include harlequin shrimp, emperor angelfish, day octopus, sea krait, spotfin lionfish, and regal angelfish. Boat access is required for all dives, which typically last 35 minutes.

Koh Bon Ridge is a diverse site featuring a reef, wall, and pinnacle topography. Divers can navigate from the North Ridge across the West Ridge and into the bay. The site offers depths ranging from 5 to 45 metres, with an average depth of 25 metres. Access is strictly by boat due to its distance from shore. Conditions are variable, with strong currents and potential down currents, making this site suitable for intermediate divers. Visibility typically ranges between 10 and 40 metres. Water temperatures remain consistent between 29 and 30C, though thermoclines and cold water gusts associated with plankton blooms occur. Night diving is available at this location.

Torinla Reef at Koh Bon is a marine dive site situated 60 kilometres from the shore. The reef features depths ranging from 5 to 20 metres, with an average depth of 18 metres. Divers should expect moderate currents and visibility typically between 20 and 30 metres. Access to this site is by boat only, and the location is suited for intermediate divers. Hazards include the depth, sharp coral, and strong currents. Water temperatures remain consistent throughout the year, ranging between 29 and 30 degrees Celsius.

HTMS Phra Thong is an artificial reef and wreck site located 5000 metres from the shore of Koh Tachai. The site is suitable for intermediate divers, with depths ranging from 16 to 28 metres and an average depth of 22 metres. Access is by boat only. Divers should be aware of moderate currents and potential hazards including entanglement and sharp coral. Visibility at the site typically fluctuates between 10 and 25 metres. A standard dive duration is approximately 50 minutes. Water temperatures remain consistent throughout the year, ranging from 27 to 30 degrees Celsius.

The HTMS Phratong is a decommissioned naval vessel resting in the Andaman Sea as an artificial reef. The wreck sits at depths between 16 and 27 metres, with an average depth of 22 metres. Access is by boat only, and the site is reserved for advanced divers with wreck certification. Visibility ranges from 10 to 30 metres, and currents are typically mild. Divers must manage depth and no-decompression limits carefully. The structure features sharp edges, and penetration requires appropriate training and lighting equipment due to the overhead environment. Water temperatures range from 28C to 31C, though local conditions can vary.