Marimbani - Mafia Island

Pety Reef, up on Menjangan’s north side, is one of those spots we always try to hit when we're in the area. It's a wall dive, mostly, dropping down to about 20 metres, and the coral here is just spectacular. We're talking huge stands of staghorn coral, some of the biggest table corals you'll see, and an explosion of colour from all the smaller stuff. It really does feel like diving through a meticulously kept garden. We’ve had some fantastic encounters here. The anemonefish are a given, always fun to watch them darting in and out of their homes, but we've also spotted more unusual critters like the orange convict reefgoby and belly-spotted pygmy-gobies tucked into crevices if you take your time. Look out for the spined fiddler crabs too, they're surprisingly charismatic. While we usually see schools of mackerel cruising by, we've also been lucky enough to spot a white-tip reef shark or two patrolling the deeper sections of the wall. Current here can be light to medium, so it’s a comfortable drift most days, making it great for photographers or those who just want to relax and soak it all in. Visibility generally sits around 17 metres, which is plenty to appreciate the scale of the wall. Pety Reef is a solid pick for anyone who loves healthy coral and enjoys a good wall dive without too much fuss.

Location: Mafia Island, Tanzania, Indian Ocean & East Africa
Coordinates: -7.954900, 39.757500
Type: reef

Marine Protected Area: Mafia Island

Best Time to Dive in Mafia Island

The warmest water temperatures in Mafia Island occur in January, averaging 28.8°C. The coolest conditions are in December at 28.8°C.

Monthly Water Temperatures

January: 28.8°C (air: 27.8°C)
February: 28.8°C (air: 28.0°C)
March: 28.8°C (air: 27.8°C)
April: 28.8°C (air: 27.0°C)
May: 28.8°C (air: 26.9°C)
June: 28.8°C (air: 26.0°C)
July: 28.8°C (air: 25.2°C)
August: 28.8°C (air: 25.0°C)
September: 28.8°C (air: 25.3°C)
October: 28.8°C (air: 26.1°C)
November: 28.8°C (air: 27.0°C)
December: 28.8°C (air: 27.7°C)

Nearest Dive Centres to Marimbani

Marine Life in Mafia Island

Home to 165 recorded species including 94 hard corals, 63 reef fish, 3 sharks & rays, 2 jellyfish, 1 other, 1 whales & dolphins.

Notable Species

Green Turtle (Chelonia mydas)
Allison's Tuna (Thunnus albacares) - Reef Fish
Whale Shark (Rhincodon typus) - Sharks & Rays
Stripy (Katsuwonus pelamis) - Reef Fish
Bigeye tuna (Thunnus obesus) - Reef Fish
Bullet Mackerel (Auxis thazard) - Reef Fish
Tuna (Thunnus alalunga) - Reef Fish
Sperm Whale (Physeter macrocephalus) - Whales & Dolphins
Tail-spot Squirrelfish (Sargocentron caudimaculatum) - Reef Fish
Cauliflower coral (Pocillopora verrucosa) - Hard Corals
Smooth cauliflower coral (Stylophora pistillata) - Hard Corals
Stony coral (Porites cylindrica) - Hard Corals
Stony coral (Porites lutea) - Hard Corals
Larger star coral (Favites pentagona) - Hard Corals
Staghorn coral (Acropora aspera) - Hard Corals
Staghorn coral (Acropora listeri) - Hard Corals
Birdsnest coral (Seriatopora caliendrum) - Hard Corals
Thin birdsnest coral (Seriatopora hystrix) - Hard Corals
Staghorn coral (Acropora polystoma) - Hard Corals
Closed brain coral (Leptoria phrygia) - Hard Corals

Recommended Packing List for Marimbani

Based on average water temperature of 28.8°C.

Shorty or Rashguard - warm 29°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