Lake Cress

Rorippa aquatica

stem plant foreground

(Eaton) E.J. Palmer & Steyerm.

Other scientific names:Cochlearia armoracia var. aquatica Eaton, Armoracia aquatica (Eaton) Wiegand, Neobeckia aquatica (Eaton) Greene, Armoracia americana, Armoracia aquatica, Armoracia aquatica capillifolia

A rosette of soft leaves that change shape with conditions — from whole and rounded to deeply cut, sometimes on the same plant. It comes from cool North American backwaters and grows very slowly.

Light: medium–high
Difficulty: easy
Temperature: 4 – 27 °C

Leaf colourgreen

Plant typestem plant

Growth ratevery slow

Tolerates lightmedium – high

pH6 – 7

Carbonate hardness2 – 14 °dKH

General hardness0 – 30 °dGH

Placementforeground

Propagationplantlets on leaves, cuttings

Grows emersedyes

Appearance

Light green leaves in a low rosette; their outline varies from a simple oval to a feather cut almost to the midrib, depending on light, temperature and how the plant was grown.

Keeping

Easy but very slow, which is exactly what makes it useful at the front of a tank: it stays where it is put for months. It wants a nutritious substrate, moderate light and cool water — warm tanks suit it least. Carbon dioxide is not needed.

Placement

The front of the tank, singly or in a small group, in an unheated or cool aquarium.

Propagation

It does most of it itself: young plants form on the leaves, drop off and root. Cuttings also take.

Water conditions match

The water suits 794 of 1249 species in the catalogue — these are the ones people look up most often.

Butterflyfish Julii Corydoras Red-finned Parotocinclus Gastromyzon monticola Egg-shaped Goldfish Flame Tetra Gardner's Killifish African Tetra Hypsolebias picturatus Common Zacco Labeo Bicolor Gambusia Flying barb Gastromyzon scitulus Albino Zebra Danio Geophagus Brokopondo Homaloptera bilineata Red-tailed Rasbora Boraras naevus Lampeye Killifish Spotted Raphael Catfish Corydoras melanotaenia Festivum cichlid Pseudomugil paskai

Will eat this plant

These species damage plants, especially when their diet is short of vegetable food.

Bengal Loach Zebra Loach Burmese Border Loach Emperor Botia Marbled Headstander Pellegrin's Leporinus Leporinus striatus False Black Tetra Common Metynnis Mylossoma duriventre Red Whiptail Catfish Moonlight Gourami Melanotaenia parva

Will uproot it

These species dig through the substrate and pull rooted plants out.

Marble Loach Peacock Eel Forktail Loach Guntea Loach Long-nosed Loach Horseface Loach Pearlscale Black Moor Goldfish Shubunkin Painted Pleco Featherfin Synodontis Reddish Mystus Catfish Blue Acara Pearl Cichlid Red-spotted Cichlid Haplochromis philander Red Chromide Jack Dempsey cichlid

The same plant with a different look: light, water and care are shared with the species.

Other varieties: Rorippa aquatica Topf