Rush-like perennial Eleocharis, or sedges, occur naturally in and around ponds and lakes. Some are quite large and enjoyed by backyard pond keepers. Smaller varieties such as hairgrass are perfectly suited for use by the home aquascape enthusiast. As the name suggests, this plant is grass-like in structure. Easy to grow and maintain, newly installed hairgrass adds attractive clumps of greenery to any freshwater aquarium. Left to their own devices, the plants soon spread to form thick, lush carpeting on everything that gets in their way.
Plant clumps of hairgrass directly into your aquarium's substrate at roughly the same depth they occupied in the grower containers. Root balls should be about ¼-inch in diameter. Space them about 1 inch apart and the plants will soon spread to fill the gaps in between each other.
Maintain the aquarium temperature around 72 to 83 degrees F. This works out well for habitats housing tropical animals, which thrive at the same water temperature. Hairgrass isn't a good choice for unheated aquaria, such as those housing cold hardy goldfish or koi. Lighting and pH requirements are adequately met in the typical home tropical aquarium.
Prune your hairgrass of any brown material as may occur. Snip it off with clean, sharp scissors. Don't just pinch it off, which might cause injury to the stem and invite fatal plant rot. Should the plants grow a little too tall for your taste, just trim them back to the desired height.
Separate the babies that sprout nearby by way of runners to create new plants. Just snip the runner in the substrate with sharp, clean scissors to divide parent from offspring.
Add non-vegetarian algae eating animals if excessive algal growth occurs on hairgrass.