A famous and undemanding coldwater plant for a long time, with only limited hardiness, Elodea densa develops free-floating or embedded, however can also be kept at higher temperatures for brief periods. It adjusts to delicate, corrosive water rich in lime with higher pH-values. In agreeable conditions the species is an excellent oxygen supplier on account of its rapid growth.
Egeria densa is a good plant for beginners, and its rapid growth helps create a balance in the aquarium from the start. It can also help prevent algae because it absorbs a great number of nutrients from the water. The plant secretes antibiotic substances which can help prevent blue-green algae (a type of bacteria). The growth rate depends largely on the amount of light and nutrition available. Growth does not stop in unfavourable conditions, but the plant turns light in colour and the tendrils grow thin.