American Frogbit (Limnobium spongia) - Portion Cup

American Frogbit (Limnobium spongia) is a beginner-friendly floating plant with rounded green leaves and long, feathery roots. It creates natural shade and shelter for fry, shrimp, bettas, gouramis, and other calm freshwater residents while drawing excess nutrients directly from the water column.

Explore more easy greenery in our freshwater aquarium plant collection.

Care Guide

• Placement: Float the plants directly on the water surface. Do not bury the roots or leaves.
• Flow: Keep surface movement gentle. Strong filter output can push the leaves underwater and cause damage or rot.
• Light: Moderate light supports compact, healthy growth. Thin the mat regularly so plants below still receive light.
• CO2: Injected CO2 is not required because the leaves use carbon dioxide from the air.
• Fertilizer: American Frogbit feeds from the water column. A complete liquid fertilizer helps when nutrients are limited.
• Maintenance: Remove yellow leaves and excess daughter plants as needed. Long roots may be trimmed with clean scissors.
• Propagation: Healthy plants spread by runners that form new rosettes.

Specifications

Placement & Companions

Use American Frogbit to soften bright lighting, provide cover for shy fish, and give small shrimp or fry a dense root zone to explore. It works especially well in calm community aquariums, betta tanks, shrimp tanks, and nature-style displays. For a smaller textured floater, consider Salvinia. For very fast surface coverage, see our Duckweed portion cup.

Recommended Supplies

• Seachem Flourish for broad water-column trace nutrition
• Freshwater aquarium plants for more easy planted-tank options

FAQ

Do I plant Frogbit in the substrate?
No. Place it directly on the water surface and let the roots hang freely.

Does American Frogbit need injected CO2?
No. It takes carbon dioxide from the air, so stable light and water-column nutrients matter more.

Why are the leaves turning brown or soft?
Strong flow, repeated splashing, submerged leaves, or a nutrient shortage are common causes. Keep the leaves floating and reduce direct filter spray.

Is this the same as Amazon Frogbit?
No. This listing is American Frogbit, Limnobium spongia, a North American species. Amazon Frogbit is a different species commonly sold as Limnobium laevigatum.

Live plants naturally vary in leaf size, root length, and number of rosettes in each portion cup.