Amazon frogbit (Limnobium laeviatum) is an easy to care for, floating aquarium plant. It is native to Central and South America, though in recent years it has reported in North America as an invasive species. It is now found throughout much of California, and continues to spread via releases and escapes from the aquarium trade.
This plant is very popular as an ornamental plant, and is often found in both ponds and aquariums. The juvenile plants grow leaves that lie flat with the water, while the more mature plants will have emergent leaves above the water. They produce small, white flowers upon reaching maturity, which makes them one of the most attractive floating plants available.
Amazon frogbit can grow up to 20 inches (50 cm) in the home aquarium, and it can easily spread across the entire surface of an aquarium. Because of this, it needs to be regularly thinned. If it is left unchecked, it will completely cover the surface of an aquarium, which can lead to oxygen depletion. It will also prevent any other plants in the aquarium from receiving any light.
While this plant is relatively easy to care for, there are certain steps that must be taken to ensure that it thrives. The most important aspect of caring for this plant is to make sure that the top of plant is kept dry at all times. If the tops of this plant stay wet for any length of time, it will begin to rot. So care must be taken when changing the water in a tank with Amazon frogbit, or any splashing from a filter in the tank.
This plant is also more susceptible to snails than many of the widely available aquarium plants. If it is kept in a tank with a large snail population, you may begin to see the underside of the plant being eaten. This can be avoided by keeping the plant towards the center of an aquarium, or keeping more plant friendly snails like Malaysian trumpet snails.
Since it is a floating plant, there is no need to add CO2 to the aquarium. However, fertilizer should be added to the water regularly, and it’s always a good idea to add a high quality fertilizer like Seachem Flourish during weekly water changes.
Lighting isn’t as much of a concern for a floating plant, since it normally sits so close to the lighting. With that being said, it does best when provided with moderate to high lighting. Any lights used should be full spectrum T5 or T8 bulbs, though some people have reported success with LED lights in recent years.
Amazon frogbit reproduces sexually through flower pollination and seed production, although this can be difficult to reproduce in the home aquarium. In an aquarium, most reproduction will occur through plant stem fragmentation. Smaller plants will break off the main plant, and they will grow to form full plants in their new location.