Shoal Grass features thin, flat bladed leaves that resemble terrestrial grass, reaching heights to about 12". It is an important sea grass in that it is a pioneer colonizer of disturbed areas where Turtle Grass and Manatee Grass cannot grow. It is often found in waters too shallow or too deep for other grasses to grow and can survive the widest range of salinity of all sea grasses. It can also survive direct exposure to air and tropical sunlight at low tide levels. Its popularity for use in the aquarium is growing, as it can do well in shallower substrates (3" minimum) because the root system only extends about 4" into the substrate.
Just like other seagrass, the root system spreads by lateral growth of the rhizomes at their ends and is the most common form of reproduction. Sand beds that are rich in organic material are best, but plants can be fertilized by inorganic means such as dry and liquid plant food. As with Turtle Grass, there is evidence of the presence of nitrogen-fixing anaerobic microbes on their roots and rhizomes, which help to supply nitrogen to nearby grass beds. Free floating fragments remain viable for several weeks and can even repopulate sand beds.
This characteristic makes it an ideal specimen for the aquarium as it is very hardy and adaptable. Most specimens find their way into the aquarium trade by the collection of "drift fragments" collected after storms and by boaters disturbing grass beds.