How long do Diamondback Terrapins live?
Diamondback terrapins live 25-40 years and reach 4-9 inches (10-23 cm) shell length, females notably larger; adults weigh 0.3-1 kg.
What do Diamondback Terrapins eat?
They are largely carnivorous: mollusks, crustaceans, fish, snails, and aquatic pellets. Feed adults every other day to 3 times weekly; dust with calcium. They need dietary calcium (shell-building) and benefit from cuttlebone. Avoid all-meat-only excess and provide some greens.
Diamondback Terrapin enclosure setup
Adults need a 75-gallon-plus aquarium with brackish water (add aquarium salt to about 1/4-1/2 seawater strength, roughly 10-15 ppt, monitored with a hydrometer), strong filtration, a submersible heater at 72-78°F (22-26°C), and a basking dock with a lamp to 85-90°F (29-32°C). Strong UVB is required. Provide a secure lid.
Common mistakes with Diamondback Terrapins
Key errors: keeping them in plain freshwater or full seawater (they need brackish — wrong salinity causes skin/eye disease), weak filtration, no UVB, and acquiring wild-collected animals where regulated.
Beginner mistakes to avoid
- Wrong salinity — they need brackish, not fresh or full seawater.
- Weak filtration — brackish water fouls and causes disease.
- No UVB — metabolic bone disease.
- Wild-collected / unpermitted — regulated in many states.