Cave of the Kastom Shark - Iron Bottom Sound

Gallinazo is rough around the edges, a site that demands respect but gives back in spades. It’s about a 25-minute boat ride from Santa Maria, and you'll want to be ready to drop fast – the sea hits hard here. We’re talking a maximum depth of 13 metres, but don’t let that fool you. This is strictly for advanced divers who are comfortable with quick entries and often challenging conditions. What we love about Gallinazo is the sheer density of the kelp forest. It’s a proper underwater jungle, a sensory overload as the fronds sway, creating these shifting patterns of light and shadow. Visibility averages around 4 metres, which sounds low, but it actually adds to the drama, making every discovery feel more intimate. We've spent hours here just watching Pacific cornetfish ghost through the kelp, their long snouts probing for smaller prey. Look closely on the rocky bottom and you’ll spot Pacific speckled crabs scuttling, while barred pipefish play hide and seek amongst the stalks. It’s a cool, moody dive, completely different from your typical tropical reef, and our pick for something truly unique in Peru.

Location: Iron Bottom Sound, Solomon Islands, Central & South Pacific
Coordinates: -8.341400, 157.501200
Type: cave

Marine Protected Area: Ha'apai

Best Time to Dive in Iron Bottom Sound

The warmest water temperatures in Iron Bottom Sound occur in January, averaging 30.5°C. The coolest conditions are in December at 30.5°C.

Monthly Water Temperatures

January: 30.5°C (air: 26.9°C)
February: 30.5°C (air: 26.7°C)
March: 30.5°C (air: 26.7°C)
April: 30.5°C (air: 26.8°C)
May: 30.5°C (air: 26.9°C)
June: 30.5°C (air: 26.5°C)
July: 30.5°C (air: 26.5°C)
August: 30.5°C (air: 26.3°C)
September: 30.5°C (air: 26.5°C)
October: 30.5°C (air: 26.7°C)
November: 30.5°C (air: 26.7°C)
December: 30.5°C (air: 26.9°C)

Nearby Dive Sites in Iron Bottom Sound

Nearest Dive Centres to Cave of the Kastom Shark

Marine Life in Iron Bottom Sound

Home to 415 recorded species including 320 reef fish, 29 hard corals, 18 sea snails & nudibranchs, 16 sea cucumbers, 7 seagrass & algae, 5 clams & mussels.

Notable Species

Blue-lined Surgeonfish (Acanthurus lineatus) - Reef Fish
Bristle-toothed Surgeonfish (Ctenochaetus striatus) - Reef Fish
Blue and Gold Fusilier (Caesio caerulaurea) - Reef Fish
Boring Clam (Tridacna crocea) - Clams & Mussels
Orange-lined Triggerfish (Balistapus undulatus) - Reef Fish
Dusky Parrotfish (Scarus niger) - Reef Fish
beautiful fusilier (Caesio teres) - Reef Fish
Blue-lined Tang (Zebrasoma scopas) - Reef Fish
Rainbowfish (Halichoeres hortulanus) - Reef Fish
Redfin Butterflyfish (Chaetodon lunulatus) - Reef Fish
Burrowing urchin (Echinometra mathaei) - Sea Urchins
Small giant clam (Tridacna maxima) - Clams & Mussels
Kihikihi (Zanclus cornutus) - Reef Fish
Latticed Butterflyfish (Chaetodon rafflesii) - Reef Fish
Bleeker's Parrotfish (Chlorurus bleekeri) - Reef Fish
Butterfly fish (Chaetodon vagabundus) - Reef Fish
Black-barred Surgeonfish (Acanthurus nigricauda) - Reef Fish
Mimic Surgeonfish (Acanthurus pyroferus) - Reef Fish
Triangular Butterflyfish (Chaetodon baronessa) - Reef Fish
Wrasse (Labroides dimidiatus) - Reef Fish

Recommended Packing List for Cave of the Kastom Shark

Based on average water temperature of 30.5°C.

Shorty or Rashguard - warm 30°C water needs minimal exposure protection
Mask - essential for every dive
Fins
BCD - buoyancy compensator
Regulator - your most safety-critical piece of gear
Dive Computer - tracks depth, time, and NDL
Surface Marker Buoy (SMB) - essential for boat pickups
Dive Torch - useful for crevices and colour at depth
Underwater Camera - capture your diving memories