Adonis pleco, polka dot lyre-tail pleco (Acanthicus adonis) care guide

Group
Freshwater fish
Other names
Polka dot lyre-tail pleco, Adonis pleco, Lyre-tail pleco
Family
Loricariidae (suckermouth armoured catfishes)
Origin
Lower Rio Tocantins and the lower Amazon, Pará, Brazil (type locality Cametá on the Tocantins).
Water
freshwater
Maximum size
100 cm
Temperature
20–30°C
pH
6–7.8
Hardness
3–18 dGH (estimated)
Minimum tank
3800 litres
Care level
expert
Temperament
aggressive

Care

Juveniles, with their black bodies, white spots and long lyre-shaped tail, are some of the most eye-catching plecos sold, but this is one of the largest loricariids in the hobby. PlanetCatfish gives a maximum of about 100 cm standard length. It grows slowly, but it does get there, and an adult needs a huge aquarium or indoor pond – PlanetCatfish suggests well over 1,000 US gallons (about 3,800 litres) for a single adult male. Furnish with large pieces of bogwood and branches and an inert sand base. Any rockwork must be heavy (at least the weight of a house brick) and well bedded down, as an adult can move almost anything. Filtration must be powerful and water changes large and frequent; this is a messy fish that needs very clean, well-oxygenated water. Aim for about 20–30 °C and pH 6.0–7.8. It has no adipose fin. Acanthicus adonis is told from its relative A. hystrix by the white spots on young fish and a more pointed snout; the spots fade as the fish grows, so large adults can be hard to identify. Males are more heavily spined all over the body, including the cheek (interopercular) area, but looking at the genital area is the easiest way to sex them. When buying a juvenile, make sure it is plump and feeding well. It has not been assessed on the IUCN Red List. Selling: our policies require the adult size and long-term tank needs to be stated clearly in the listing. Large fish must travel by a specialist live-animal courier (see the Livestock shipping guide). Sources: PlanetCatfish (planetcatfish.com/common/species.php?speciesid=277). Checked October 2026.

Diet

An omnivore that eats almost anything. Offer a good sinking pellet or wafer as the staple, with vegetables, fruit, mussels and other molluscs, prawns and pieces of fish. It also rasps at wood, so keep bogwood in the tank.

Breeding

It has been bred in captivity, but only in ponds or very large aquaria. Males are aggressive towards females, which makes spawning hard to achieve. Like other large plecos it is a cave spawner, with the male guarding the eggs.

Compatibility and tank mates

Highly aggressive, especially towards other bottom dwellers. Keep it alone or with large, robust midwater fish that will not compete for space on the bottom. Do not mix with other large plecos or other competitive loricariids.

Last updated 5 October 2026. Community-edited care guide on Aquatic-Auctions.

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  • 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.
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