Red root floater

Quick facts

Max height

3 cm

Growth rate

moderate

Difficulty

beginner

Placement

floating

Propagation

fragmentation

Water parameters

Temperature

20–28°C

pH

6.0 to 7.5

Hardness

1 to 12 dGH

Light and nutrients

Lighting

medium

CO2

not needed

Substrate

floating

Feeding

feeds from the water column (use liquid fertilizer)

Substrate

What this plant roots into (or attaches to). The substrate affects both plant nutrition and water chemistry; see each linked page for full effects.

This plant feeds primarily from the water column, so substrate choice matters more for its fish-tank compatibility than for plant nutrition.

With fish

Plant-eating fish

will be eaten by mollies, silver dollars, large goldfish, and other plant-grazers

Diggers (corydoras, loaches)

fine - root system or attachment style handles it

Root-disturbing fish

tolerates fish that disturb roots

Habitat

Native to Central and South America, found floating on the surface of slow-moving rivers, ponds, and marshes. The species (Phyllanthus fluitans) is a floating plant with small, round leaves (1–3 cm diameter) that develop vivid red coloring on the undersides and upper surfaces under strong light. The red coloring is the feature that distinguishes it from other small floaters like salvinia or duckweed and makes it popular as a decorative surface plant. The trailing roots are red to burgundy, adding to the ornamental appeal. Red root floater spreads by budding daughter plants connected by short stolons, forming loose mats on the water surface. Growth is slower than duckweed but faster than most submerged plants. The species was relatively unknown in the aquarium hobby until the 2010s, when it gained popularity through social media posts showcasing the vivid red coloring. It's now widely available from online aquatic plant retailers and hobbyist trades. P. fluitans is not considered invasive in most temperate regions because it's cold-sensitive (dies below about 15°C).

Outdoor pond use

This species transitions to outdoor ponds well, not just indoor aquariums.

Outdoor pond zones (USDA)

8 to 13 (winter low around -12°C or warmer)

Below the minimum zone, the plant won't overwinter outdoors but can still be grown seasonally and overwintered indoors. Several pond-friendly species (water hyacinth, water lettuce, parrot's feather) are regulated as noxious in some jurisdictions; check the legality data on the profile before releasing anything to an outdoor body of water.

Care notes

A decorative floating plant prized for its red coloring. Moderate to high light is essential for the red color; under low light, the leaves stay green and the plant loses its visual distinction from other floaters. Surface agitation from strong filter outflow pushes the plants around and damages roots; baffle the outflow or create a calm surface zone using airline tubing or a floating ring. The red color intensifies under iron-rich conditions; liquid iron supplementation in the water column makes a visible difference. Temperature: 20–30°C. pH 6.0-7.5. Prefers soft to moderately hard water. Low surface agitation and high light produce the most vivid red coloring. The plant absorbs nutrients from the water column through its roots, helping to reduce nitrate and phosphate. Growth rate is moderate; thin the population every 1-2 weeks to prevent complete surface coverage that blocks light to submerged plants. Propagation is automatic through daughter plants. Compatible with all fish. The trailing red roots provide shelter for fry and shrimp. Available from aquatic plant retailers and hobbyist trades.

Further reading

• How to cycle a fish tank
• Water chemistry for fishkeepers: pH, GH, KH, and what they mean