Water parameters
Overview
The scarlet pleco was known for years by the number L025 and was described in 2014 as Pseudacanthicus pirarara. Its body is covered with hard, spiny plates (the name "cactus pleco" comes from this); the red-orange colors on its fins make it a much sought-after species.
Juveniles are expensive and sold small, but adults are large, powerful fish reaching 45 cm standard length. Because of its territorial nature and size, it is only for experienced keepers and very large aquariums.
Tank Setup
- At least 1000 liters and 200 cm length for one adult.
- Very powerful filtration, flow and aeration.
- Large caves and sturdy rock piles; 27–29°C.
Diet
An omnivore leaning toward a carnivorous diet. Make pieces of mussel, shrimp and fish, krill, bloodworms and protein-rich tablets the staple; a small amount of vegetables can also be given.
Behavior and Compatibility
Powerful and territorial. It can show serious aggression toward its own kind and other plecos; with its spiny body it can injure other bottom dwellers.
Good companions: Large, fast, robust fish: large Central and South American cichlids, large characins (in a very large aquarium).
Avoid: Other plecos, small and slow bottom dwellers, shrimp, snails.
A short profile for this species
The Scarlet Pleco (L025) page has the basics, but the sections below have not been written yet. If you keep this species, write a section from your own experience; it will be published under your name after editor approval.
Tank mates
This list is calculated automatically from the species profile and grows as new species are added to the catalog. Try it in the planner for a definite answer.
Usually compatible
Emerald Betta
Festivum
Altum Angelfish
Firemouth Cichlid
Banded Jewel Cichlid
Buffalohead Cichlid
Chocolate Cichlid
Rainbow Cichlid
Threadfin Acara
Should not be kept together
Hobbyist notes
Things you won't find in books, learned by trial and error. The most helpful ones are on top.
Change history and contributors
- Page created · October 16, 2026







