Cartilage Cartilage is a flexible but strong supportive connective tissue. Unlike bone and all other connective tissue types, cartilage is avascular, lacking blood vessels. For this reason alone, cartilage does not possess the regenerative capacity of bone or the other connective tissue types. Remember, nutrient delivery is essential for tissue repair.
The flounder is a species of flatfish that is found in the coastal waters of the northern Atlantic and Pacific Oceans. Flounder are found hiding on the ocean floor at depths from shallow coral reefs to the deepest trench on Earth.
Spotted puffer fish are sold as freshwater puffers. And in parts of their range, they do sometimes live in freshwater. However, they really do their best in brackish water -- water with some salt in it, but less than full-strength seawater. Water with a specific gravity of 1.005 suits them.