Mermaid Weed

Geographical Origin and Habitat: Widely distributed in the Americas, from southern Canada through the USA to the Caribbean and Central America. Found in ditches and swamps.

Taxonomy & Genetics: Belonging to the family Haloragaceae, genus Proserpinaca. Commonly referred to as Mermaid Weed due to its leaf appearance.

Physical Structure: A moderate to slow-growing stem plant. Submersed leaves are deeply serrated and comb-like (pectinate).

Color & Texture: Foliage turns from yellowish-orange to a striking coppery-red under high light. Features a highly textured, needle-comb appearance.

Lighting & CO2: High light is required to develop both the intense copper color and the serrated leaf structure. CO2 injection is essential.

Nutrition & Substrate: Prefers a nutrient-rich substrate. Responds well to iron supplementation in the water column to boost red hues.

Water Chemistry: Adaptable. pH should be kept at 5.5-7.5, with soft to medium hardness. Water temperature range of 20-28 °C is optimal.

Space Management & Placement: Ideal for the midground in small groups. Its unique leaf shape makes it an excellent contrast plant against broad-leaved species.

Pruning: Trim stem tops and replant. Because of its slower growth rate, pruning is less frequent than with other stem plants.

Risks & Diseases: Under low light or lack of CO2, the leaves become less serrated, wider, and turn green, losing their ornamental appeal.