Scientists call long-spined sea urchins "the lawn mowers of the reefs" because they eat algae that could otherwise smother reef ecosystems and kill corals. That's why researchers affiliated with the University of Florida Tropical Aquaculture Lab (TAL), who work at the Florida Aquarium's Conservation Campus in Apollo Beach, are trying to raise as many urchins as possible. Aaron Pilnick, a post-doctoral researcher at TAL, led newly published research that identifies substrates that help long-spined sea urchins -- scientifically known as Diadema -- grow from larvae to juveniles in a lab setting. A substrate is the surface on the sea floor on which an organism lives or obtains its nourishment.