As the name says, this liverwort has long been used as a floating(fluitans) plant in aquariums and ponds. Under optimal conditions any branch or fragment can form thick mats under the surface which provide shade and a hiding place for babies.

The tight growth pattern has been used by, among others, Takashi Amano, to form dense bright green carpets. This is accomplished by trapping the riccia plants under a mesh tied to wood or flat stones. However, the plant requires frequent trimming, otherwise the bottom plants will die and the riccia carpet will float to the surface. Nevertheless, this plant is spectacular when submersed, as it pearls easily.

The plant remains relatively skinny if water column nutrients are low. For submersed growth CO2 injection is recommended.

As with many liverworts, high doses of liquid carbon, hydrogen peroxide or bleach dips will destroy the plant completely. Due to its structure this plant is likely to gather hair algae. Consider carefully before introducing this plant for the first time in the aquarium as it can be quite tedious to get rid of.

Photo 1: Riccia fluitans submersed pearling. Source : Mihai Zamfir (Allwissend), 2017. All rights reserved. Used with permission.