What happens to a starfish to become a fossil?

What does it mean when a fish stays at the bottom of the aquarium? Is it safe to spray glyphosate on pond weeds? Is a dogfish egg-case man made? Where can you watch 2 girls 100 eels? Can you use dissolved rock salt in your salt water aquarium? What do the hammerhead shark eat? How do sediment traps work? Can a shark never get sick? How many bones does a clownfish have? Do great white sharks live in the North Sea? Is a manatee found in marine or freshwater? What is fish terrine? What is the record for fish fingers eaten in 1 hour? Is a blob-fish a mammal? How do great white shark sleep? What types of sharks are in key west? What would happen if you put a female and a male Betta fish together? How much gravel should you put in a 14 gallon aquarium please? What is the difference between a tropical and a freshwater fish? Is shark edible?