Mainit Bubble Springs

A unique site combining volcanic hot springs — with bubbles and hot water rising from the sand — and a 70-meter sheer wall covered in gorgonias, sponges, and sea whips, home to banded sea snakes, anglerfish, and turtles.

Overview

Mainit Bubble Springs is one of Anilao’s most distinctive dive sites, combining two unusual features. The first is the volcanic hot springs — streams of bubbles and warm water rise from the sandy bottom, a reminder of the area’s volcanic geology. The second is a sheer wall approximately 70 meters in length, dropping from 22 to 30 meters and covered in gorgonias, sponges, and sea whips. The combination of volcanic activity and rich wall diving creates a site unlike anything else in the Anilao area. Banded sea snakes are regularly encountered, and the wall supports anglerfish, leaf fish, batfish, turtles, and nudibranchs.

Site Information

• Location: Mainit, Anilao, Batangas, Philippines
• Entry Type: Boat dive
• Site Type: Wall dive
• Difficulty Level: Intermediate
• Maximum Depth: 30 meters
• Typical Visibility: 10-20 meters
• Water Temperature: 27-29°C (warmer near hot springs)
• Current: Variable
• Best Time: November to June (dry season)

Marine Life

Banded sea snakes are regularly encountered at Mainit Bubble Springs, hunting among the rocks and coral near the hot springs. The wall is home to anglerfish, which sit camouflaged on the gorgonia-covered surface. Leaf fish — masterful mimics that sway like pieces of debris — can be found along the wall. Batfish school near the wall face. Turtles are seen resting on ledges or swimming along the wall. The wall’s gorgonias, sponges, and sea whips support a healthy population of nudibranchs. The volcanic hot springs themselves are fascinating to observe, with streams of bubbles and heated water creating visible distortion in the water column.

Dive Profile

Enter from the boat and descend to explore both features of the site. The hot springs area is in the sandy shallows, where bubbles and hot water can be seen (and felt) rising from the bottom. The wall section runs approximately 70 meters, from 22 to 30 meters depth, and is covered in gorgonias, sponges, and sea whips. Work along the wall face, scanning for anglerfish, leaf fish, and nudibranchs. Check ledges for resting turtles. Keep an eye out for banded sea snakes throughout the dive.

Entry and Exit

Access by boat from Anilao-area resorts. Enter by giant stride and descend to the site. Deploy an SMB during your safety stop for boat pickup.

Tips and Recommendations

• Feel the water near the hot springs — the temperature difference is noticeable and adds to the unique character of the dive
• The bubbles from the hot springs make for unusual photographs and video
• Banded sea snakes are not aggressive but should be given space; they need to surface regularly to breathe
• The wall section is the main attraction for marine life — budget most of your bottom time there

Safety Considerations

The volcanic hot springs produce heated water that can be surprisingly warm — avoid putting your hand directly into a concentrated vent. Banded sea snakes are venomous, though they are generally docile and pose little threat if not harassed; give them room and do not attempt to handle them. The wall drops to 30 meters, so monitor your depth and gas supply carefully. Standard wall diving precautions apply — watch for unintentional depth increases.

Photography

Mainit Bubble Springs offers genuinely unique photographic opportunities. The volcanic bubbles rising from the sand create distinctive images found at very few dive sites worldwide. Wide-angle captures the bubble streams and wall structure effectively. On the wall, anglerfish and leaf fish are excellent macro subjects. Banded sea snakes in hunting posture make dramatic portrait images. The gorgonia-covered wall provides colourful reef-scape compositions. This site rewards photographers who bring both wide-angle and macro capability.

Sources: Michael McFadyen’s Scuba Diving Web Site, AnilaoDiving.com – Mainit Bubbles Point, Blue Ribbon Divers – Bubbles Dive Site. Last updated 2026-06-25.