How do most sea invertebrates maintain water balance?

Most marine invertebrates are osmoconformers, which means that they maintain water balance through osmoregulation. The osmoregulation enables animals to live in environments, such as freshwater and terrestrial habitats and

enables many marine animals to maintain internal osmolarities different from that of seawater. The an imals that expends energy to control their internal osmolarity because its body fluids are not isoosm otic with the outside environment are called osmoregulators.