About the species

Cyperus helferi from Thailand was the first species in its genus to be taken into the aquarium hobby. It forms a rosette of long, narrow, grass-like leaves, growing 20–35 centimetres tall and 15–25 centimetres wide. The leaves are soft and follow the water movement, so in an aquarium with good flow the whole plant sways back and forth.

Facts

• Latin name: Cyperus helferi
• Plant type: Rosette plant
• Origin: Asia
• Height: 20–30 cm
• Growth rate: Slow
• Position: Background

Light requirement

Medium light requirement. Reckon on around 0.5 W per litre or a modern mid-range LED unit. Too little light gives sparse, stretched shoots and pale leaves, while the right amount keeps the plant compact and richly coloured.

CO₂ & nutrition

Added CO₂ is recommended — Tropica reckons 6–14 mg/l as a medium requirement. The plant can be grown without, but then grows more slowly and loses some of its colour. Supplement with liquid fertiliser weekly and keep iron and potassium levels up.

Planting

Plant the root ball in the substrate so the roots are covered but the crown — where the new leaves emerge — sits just above it. Burying the growth point makes the plant rot. Give it plenty of room, since the leaves spread out in a rosette.

Carefully remove the pot and rinse the rock wool off the roots before planting — leftover rock wool can otherwise hinder rooting.

Care & propagation

Cut old outer leaves off at the base once they start to look tired, and the rosette stays fresh. The plant propagates itself with daughter plants from the rootstock; separate them from the mother plant once they have their own roots and a few leaves.

Position in the aquarium

Given its mature height it belongs at the back or along the sides, where it forms a dense wall of greenery and hides equipment. In a smaller aquarium it can also be used as a solitaire in one corner.

Difficulty level

🟡 Moderate — wants stable lighting and regular fertilisation to look its best.

Delivery format

Delivered as a pot grown submerged, with the roots in rock wool. The pot holds several plants or stems that can be divided and planted separately.

Recommendation

A fine way to bring grass into an aquascape without resorting to Vallisneria, and most effective in a small group. Place it where the filter current reaches the leaves — the movement is the whole point of this plant.