Tidepool Tim says, "Beach plants must be able to tolerate salinity, giving them access to a relatively competition-free environment. The name for a salt tolerant plant is "hydrophyte." There are many fascinating adaptations these plants have developed. For example, Spartina plants have salt stores in their cells to draw in fresh water and prevent infiltration of marine salts. They can also excrete salt from their cells to remain in homeostasis! These plants are advantageous for tanks because they have root masses which pull oxygen from the water's surface and bring it down to the aquarium substrate."