Tropical Asia, Africa and the Americas; naturalised in Spain
Water
freshwater
Maximum size
50 cm
Temperature
20–30°C
pH
6–7.5
Hardness
2–12 dGH (estimate)
Care level
expert
Lighting
High light; CO2 likely to help
Care
Monarch redstem (family Lythraceae) is an annual herb of marshes, swamps, rice fields and watercourses at low altitudes across tropical Asia, Africa and the Americas. It is slender, upright and branched, 10–50 cm tall, often tinged purple, with narrow leaves up to 3.5 cm and tiny greenish or purplish flowers clustered in the leaf axils. Wikipedia says nothing about aquarium use. Being an annual of seasonally wet ground, it may not last long submerged; expect a short-lived plant that does best with strong light. Water figures are our estimate, not from the sources. Sources: Wikipedia (en.wikipedia.org/wiki/Ammanniabaccifera); Wikipedia, List of freshwater aquarium plant species. Checked October 2026.
Breeding
Mainly from seed as an annual; cuttings may root.
Compatibility and tank mates
Soft stems are eaten by goldfish, large cichlids and herbivorous fish. Good with shrimp, snails and small community fish in tropical tanks.
Last updated 8 October 2026. Community-edited care guide on Aquatic-Auctions.
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Items are sold by auction, buy it now or classified advert, by hobbyist and business sellers in the UK.
Buyers pay sellers directly; Aquatic-Auctions does not hold the money. Hobbyist sellers must offer PayPal and may also take cash on collection. Business sellers take PayPal (required) or cash on collection, and bank transfer only once they have a seller rating of 50 out of 100, a company and pet-selling licence checked by Aquatic-Auctions, a bank account in the company's name, and bank details approved by Aquatic-Auctions.
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Live fish and other vertebrates must be sent by specialist live-animal couriers (for example APC Overnight or DX Express), never by Royal Mail. Some invertebrates and plants may go by Royal Mail Special Delivery or 1st Class within its rules.
Banned and invasive species (for example those on the GB invasive species lists) cannot be listed, and sellers must meet the site’s animal welfare standards.
Members must be 16 or over to buy (16 and 17-year-olds with a parent or guardian’s agreement); sellers must be 18 or over.
Business sellers show their address, company details and pet-selling licence to buyers. Seller ratings run from 0 to 100: +1 for each positive feedback, −1 for each negative.
The site includes a free community species wiki with care guides (water parameters, tank size, diet, temperament, breeding).
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