Frogbit (Limnobium laevigatum) is a South American floating plant with small, round, slightly cupped leaves carried on a open rosette that sits buoyantly at the surface — a leaf form and growth habit distinct from every other floating plant in the catalog. Where Water Lettuce produces large ribbed rosettes with broad canopy drama, Salvinia produces dense interlocking mats, and Water Spangles produces a fine seamless tile, Frogbit produces an open, spaced arrangement of small individual round leaves that creates a dappled rather than solid light canopy — patches of shade and light shifting as the plant drifts. The roots hang freely below each plant in long, fine, decorative curtains that provide excellent shrimplet refuge and biofilm surface, visible from the side of the tank when the plant is positioned near the glass. It spreads at a moderate pace by producing daughter plantlets on short stolons, easier to manage than the fastest-spreading floating plants. Requires calm surface water. Fully safe with all Neocaridina, Caridina shrimp, and snails.
Not RequiredCO₂
64–82°FTemperature
Low–HighLighting
What to Expect
Growth & Behavior at the Surface
Round, slightly cupped leaves on an open rosette — Frogbit leaves are small and nearly circular with a slight cupping that catches and holds a thin film of air on the upper surface — the source of its buoyancy and the characteristic that gives individual leaves a slightly silvery sheen when viewed from above. The open rosette habit means individual plants are clearly distinguishable from one another at the surface rather than merging into a continuous mat — the plant maintains individual identity even at high colony density.
Dappled canopy rather than solid shade — the open spacing between leaves within and between rosettes allows light to pass through in patches — creating a shifting, dappled light pattern on the substrate below that mimics natural surface cover more closely than any other floating plant in the catalog. For submerged plants that require some light, Frogbit provides shade without blackout — a more forgiving overhead presence than dense mat-forming floaters. The dappled light pattern is particularly visible and attractive in tanks with strong overhead lighting.
Long, fine roots trail visibly below each plant — Frogbit produces long, unbranched white roots that hang freely below each rosette in a fine curtain extending several centimetres into the water column. The roots are decorative — visible from the side of the tank when plants are positioned near the glass — and functional, accumulating biofilm across their length and providing physical refuge that shrimplets navigate into readily. The root curtain is more open and less tangled than Water Lettuce and more visually elegant than the short modified roots of Salvinia.
Moderate spread via daughter plantlets on stolons — Frogbit propagates by extending short stolons from the parent rosette and producing daughter plantlets at their tips, which develop their own root system and eventually detach as independent plants. The spread rate is moderate — faster than Water Lettuce but significantly slower than Water Spangles or Salvinia natans — making Frogbit one of the more manageable floating plants in terms of coverage control. A small initial planting builds to meaningful surface coverage over weeks without requiring aggressive thinning from day one.
Sensitive to surface agitation — calm water essential — like all floating plants in the catalog, Frogbit requires calm surface conditions. Strong surface agitation from spray bars, powerheads, or aggressive filter outlets wets the leaves, disrupts the air film on their upper surface, and causes the plant to decline. Redirect filter outputs below the surface and away from the floating colony. A floating airline tubing ring can corral the colony into the calmest surface zone if full flow redirection is not possible.
Nutrient uptake and light diffusion complement submerged plants — Frogbit absorbs nitrates and phosphates from the water column through its root system at a moderate rate — a useful contribution to water quality in shrimp tanks between water changes, though less aggressive than the fastest-growing floaters. The dappled canopy it creates suppresses surface algae without eliminating light to submerged plants below — a more balanced overhead arrangement than opaque mat-forming floaters that can shade out midground and background plants entirely.
How to Set It Up
Getting Started
1
Redirect surface agitation before introducing plants — reposition filter outlets, spray bars, and powerheads so water movement does not disturb the surface where Frogbit will float. This is the single most important environmental condition for long-term success with any floating plant. Once flow is redirected, place Frogbit on the calm surface zone and leave it to settle — the roots will extend downward within the first day and the plant will orient itself naturally.
2
Start with a small colony and allow it to spread naturally — introduce four to six rosettes initially and allow the colony to expand by natural stolon propagation. Frogbit's moderate spread rate makes it well-suited to this approach — coverage builds steadily without immediately overwhelming the surface, giving you time to observe and decide how much coverage you want before the plant reaches that point. Thin to 50–60% surface coverage once the colony expands sufficiently.
3
Position near the glass for maximum root visibility — if the long, trailing root curtains are part of why you chose Frogbit, position the colony in the front portion of the tank near the viewing glass. The roots are visible from the side of the tank when the plant floats close to the glass — a delicate, curtain-like visual that is one of the most distinctive features of this plant and entirely invisible when the plant sits in the middle or back of the surface.
4
Thin regularly once established — remove whole rosettes — when thinning, remove complete rosettes rather than trimming individual leaves. Frogbit does not respond to leaf trimming the way stem plants do — removing leaves damages individual plants without reducing colony density. Remove whole plants at the stolon connection point, keeping the remaining colony at the coverage level you want. Removed plants can be added to breeding setups, refugiums, or shared with other hobbyists.
💡 Bonus Tip
Frogbit and Water Lettuce used together in the same tank create the most complete floating plant pairing in the catalog — Frogbit's small open rosettes and fine hanging roots filling the lighter, more open areas of the surface while Water Lettuce's large dramatic rosettes and dense root curtains anchor the corners and edges. The two plants occupy slightly different surface niches — Water Lettuce tends to drift toward edges and corners while Frogbit distributes more freely across open surface — and together produce a varied, naturalistic surface canopy that neither achieves alone at the same visual depth.
🌿
Browse more aquatic plants
Pair Frogbit with Water Lettuce, Salvinia, or submerged plants for a complete shrimp setup. Browse our Aquatic Plants collection.
→
