Hornwort (Ceratophyllum demersum) is one of the most widely kept aquarium plants in the world, producing long, branching stems of feathery, dark-green whorled needles. It is a rootless plant — absorbing all its nutrients directly from the water column — which means it can be floated freely at the surface or gently anchored in the substrate to create a background effect. It is extremely easy to grow, tolerating a wide range of water conditions, temperatures, and light levels. Its rapid growth makes it an excellent nutrient absorber, helping to suppress algae in both new and established aquariums. It also releases natural growth-inhibiting compounds that can help keep certain types of algae in check. Supplied as established cuttings, Hornwort is particularly valuable for aquariums housing fry or shrimp, as its dense, feathery growth provides natural shelter and grazing surfaces. It is equally useful in pond set-ups and coldwater aquariums where few other plant species will thrive. We recommend using lead weights to anchor these stems down.
