This is one of the favorite floating plants for aquariums and ponds. One of the reasons it has seen such success is not only its ability to quickly use the nitrate from the water, but its extensive roots also provide the perfect hiding and feeding place for fry. Unlike other floating plants, Pistia stratiotes is large enough to easily be removed.

In aquariums the plant’s leaves are rounder and float on the water surface (Photo 3). The plant stays relatively small but can reach 10cm if light is good and enough nutrients are available. The roots can reach 30cm or more. In ponds, during the summertime this plant grows large, thick leaves with 50+cm roots.

The surface of the leaf is very velvety and repels water. The leaves should not be submerged or they will rot. The plants will also have difficulty growing if the aquarium is covered and the humidity is too high. If nitrogen levels are low the plant will show yellow old leaves and reduced growth. However, if the plant is healthy, it will produce small inflorescence near the base (Photo 1).

Photo 1: Pistia stratiotes with inflorescence grown in pond, top view. Source : Mihai Zamfir (Allwissend), 2009. All rights reserved. Used with permission.
Photo 2: Pistia stratiotes grown in pond, top view. Source : Mihai Zamfir (Allwissend), 2009. All rights reserved. Used with permission.
Photo 3: Pistia stratiotes in aquarium, top view. Source : Mihai Zamfir (Allwissend), 2007. All rights reserved. Used with permission.