Pistia stratiotes L.

Water cabbage, Water lettuce, Nile cabbage, Shellflower

This tender floating aquatic is perfect for tropical aquarium. Commonly known as Water lettuce, Pistia stratiotes forms rosettes of softly hairy foliage that sit at the water’s surface with the fine roots suspended beneath. Pistia stratiotes multiplies via runners to form floating colonies, which offer excellent shade and cover for fish.

Native to: Afghanistan, Andaman Is., Angola, Argentina Northeast, Assam, Bangladesh, Belize, Benin, Bolivia, Borneo, Botswana, Brazil North, Brazil Northeast, Brazil South, Brazil Southeast, Brazil West-Central, Burkina, Burundi, Cabinda, Cambodia, Cameroon, Cape Provinces, Caprivi Strip, Central African Repu, Chad, China South-Central, China Southeast, Colombia, Comoros, Congo, Costa Rica, Cuba, Dominican Republic, East Himalaya, Ecuador, Egypt, El Salvador, Equatorial Guinea, Ethiopia, Florida, Free State, French Guiana, Gabon, Galápagos, Gambia, Ghana, Guatemala, Guinea, Guinea-Bissau, Gulf of Guinea Is., Guyana, Hainan, Haiti, Honduras, India, Ivory Coast, Jamaica, Jawa, Kenya, KwaZulu-Natal, Laccadive Is., Laos, Leeward Is., Lesotho, Liberia, Louisiana, Madagascar, Malawi, Malaya, Maldives, Mali, Maluku, Mauritania, Mauritius, Mexican Pacific Is., Mexico Central, Mexico Gulf, Mexico Northeast, Mexico Northwest, Mexico Southeast, Mexico Southwest, Mississippi, Mozambique, Myanmar, Namibia, Nansei-shoto, Nepal, Netherlands Antilles, New Guinea, Nicaragua, Nicobar Is., Niger, Nigeria, Northern Provinces, Northern Territory, Pakistan, Panamá, Paraguay, Peru, Philippines, Puerto Rico, Queensland, Rwanda, Senegal, Sierra Leone, Somalia, South China Sea, Sri Lanka, Sudan, Sulawesi, Suriname, Swaziland, Taiwan, Tanzania, Texas, Thailand, Togo, Trinidad-Tobago, Uganda, Uruguay, Venezuela, Venezuelan Antilles, Vietnam, West Himalaya, Windward Is., Zambia, Zaïre, Zimbabwe

Introduced into: Alabama, Aruba, Bermuda, Canary Is., Colorado, Hawaii, Illinois, Italy, Japan, Kazakhstan, Netherlands, New Caledonia, New York, Palestine, St.Helena, Turkey, Ukraine

Submitted by: Natasha Khardina

GPS: 25.3443413, 110.3268967

Geographical region: Eastern Asia
Drainage Basin: Pearl
River catchment: Li (Ljiang) River
Water body type: Creek
Water body name: Nameless bay
Water body part
Water body course: Lower course
Water body: tributary of: River
Tributary name: Li (Ljiang)

Type locality: Zimbabwe
Conservation status/IUCN Red List: Not Evaluated (NE)
Listed in CITES: No

Water Chemistry

Water information

Water type: Fresh water
Water color: Clear water
Water transparency: Medium
Concentration of sediments: Medium
Water temperature: 22-30 °C
Water flow/curent: None

Chemical parameters

pH: 6.5–7.5
Conductivity
GH
KH
Dissolved Oxygen

Phytology

Plant form

Floating

Plant type

Rosulate

Plant size

15-30 cm

Plant growth rate

Fast

Plant light demand

High

CO2

None

Aquarium equipment

Pistia stratiotes is a small, evergreen perennial plant with feathery roots. In Nature this plant is found free-floating in lakes, ponds, swamps, irrigation canals, or ornamental ponds, where it forms rosettes of leaves up to 10-15cm long and 10cm tall with a flowering stem up to 12cm tall.

The plant can spread quickly, especially in still water, to form quite extensive clumps.

Fry and shrimps love to hide in the shade of this plant, in the plant’s long roots. It also provides a shelter for small or shy fish to reproduce and a surface for baby shrimps to go and look for food.

Plant care

Pistia stratiotes is a free-floating plant with a rosette of obovate to spatulate, short haired leaves.

Pistia stratiotes is a clonal plant that forms small colonies with daughter plants attached to the mother plant through stolons. Dispersal is enhanced through detachment of daughter plants which form new colonies. The upper sides of the leaves are light green, while the undersides are almost white.

The floating plants have large feathery root systems which hang freely in the water. The roots extend up to 1 meter below the surface of the water and provide ample shelter for small fish. The solitary inflorescence is axillary and inconspicuous, with short peduncles in the centre of the rosette.

Pistia stratiotes produce massive quantities of seeds, which can sink to the bottom of the water and survive winter in temperate climates. Although not winter hardy, water lettuce seeds can survive under water at temperatures of at least 4°C for two months.

Water care

This plant is particularly sensitive to dissolved minerals and requires water with a salt content of 2.5 ppt. Water lettuce can help agains algae growth by providing shade for the water, and so it deprives algae of the sunlight that makes them thrive.

Water lettuce will help clean your aquarium. It consumes uneaten fish food and waste such as Ammonia, Nitrites, and Nitrates, and so, it helps with the Nitrogen cycle. That doesn’t necessarily mean that you should sit back and not change the tank’s water.

Bibliography

Comment by the expert

The plant is sometimes used locally for food, but only usually where nothing better is available. It has a range of medicinal applications and is also used as a source of organic matter and to remove toxins from polluted water.

All parts of the plant contain calcium oxalate crystals plus unknown toxins. Ingestion, in large quantities, can cause an intense burning and swelling of the lips, tongue, and throat; nausea and vomiting. Diarrhoea may also occur.

The ashes of the burnt plants can be used as a salt substitute.