Forty Fathom Grotto - Florida Springs
Forty Fathom Grotto offers cavern and cave diving in the Florida Springs system. We’ve found the main draw here is the grotto itself, a massive, dark opening leading into more extensive cave networks for properly trained divers. It's a challenging spot, best suited for experienced divers looking to explore overhead environments rather than a casual swim-through. Visibility can vary, but generally holds up well within the grotto.
- Location
- Florida Springs, United States, North America
- Coordinates
- 29.289183, -82.308750
- Type
- cave
Best Time to Dive in Florida Springs
The warmest water temperatures in Florida Springs occur in August, averaging 31.3°C. The coolest conditions are in January at 15.9°C.
Monthly Water Temperatures
- January: 15.9°C
- February: 16.7°C
- March: 20.4°C
- April: 23.4°C
- May: 26.8°C
- June: 29.5°C
- July: 30.9°C
- August: 31.3°C
- September: 29.4°C
- October: 25.6°C (air: 22.4°C)
- November: 21.3°C (air: 18.1°C)
- December: 17.6°C (air: 14.8°C)
Nearby Dive Sites in Florida Springs
- Artificial Reef CCA - Deck Barge 2 (reef)
- Betsy Ross Reef - 175 Ship YO-224 (reef)
- Betsy Ross Reef - 430 Liberty Ship (reef)
- Betsy Ross Reef - Bridge 1 (reef)
- Cape Romain Reef - 5-20m (reef)
- Capers Reef (reef)
- Capers Reef - Caisson (reef)
- Capers Reef - Coast Guard Buoy R8 (reef)
- Capers Reef - Concrete Reef Balls 1 (reef)
- Capers Reef - Landing Craft 1 (reef)
- Capers Reef - Tug Boat (reef)
- Capers Reef - Unknown Barge - 10-20m (reef)
- Charleston Nearshore Reef (reef)
- Charleston Sixty Reef - 240 Barge (reef)
- Charleston Sixty Reef - Army APCs 1 (reef)
Nearest Dive Centres to Forty Fathom Grotto
- Atlantic Pro Divers - ["PADI"]
- Blue Grotto Dive Resort
- Carolina Dive Locker
- First Coast Divers - ["PADI"]
- Island Dive Center - ["PADI"]
- Scooba Shack - SSI
Marine Life in Florida Springs
Home to 145 recorded species including 122 reef fish, 8 other, 4 sharks & rays, 3 crabs & lobsters, 2 clams & mussels, 2 sea urchins.
Notable Species
- Eastern Mosquitofish (Gambusia holbrooki) - Reef Fish
- Prodigal Son (Rachycentron canadum) - Reef Fish
- Least Killifish (Heterandria formosa) - Reef Fish
- Sailfin Molly (Poecilia latipinna) - Reef Fish
- Rainwater Killifish (Lucania parva) - Reef Fish
- Freshwater Flounder (Trinectes maculatus) - Reef Fish
- American Gulf Pipefish (Syngnathus scovelli) - Reef Fish
- Bream (Lagodon rhomboides) - Reef Fish
- Sheepshead Minnow (Cyprinodon variegatus) - Reef Fish
- Western Mosquitofish (Gambusia affinis) - Reef Fish
- Clown Goby (Microgobius gulosus) - Reef Fish
- Spot (Leiostomus xanthurus) - Reef Fish
- Silver mojarra (Eucinostomus argenteus) - Reef Fish
- Anchovy (Anchoa mitchilli) - Reef Fish
- Silver Perch (Bairdiella chrysoura) - Reef Fish
- Longnose Killifish (Fundulus similis) - Reef Fish
- Common mojarra (Eucinostomus gula) - Reef Fish
- Inland Silverside (Menidia beryllina) - Reef Fish
- Swordfish (Strongylura marina) - Reef Fish
- Black Sea Bass (Centropristis striata) - Reef Fish
Recommended Packing List for Forty Fathom Grotto
Based on average water temperature of 24.1°C, currents 1 cm/s.
- Shorty or Rashguard - warm 24°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