Otocinclus

Otocinclus, commonly called 'otos' or dwarf suckers, are small loricariid catfish distributed across river systems from Venezuela to northern Argentina in South America. Reaching only 2–5 cm, they use their sucker-like mouths to graze on soft green algae, diatoms, and biofilm from glass surfaces, plant leaves, and driftwood — making them exceptional algae controllers in planted aquariums. Unlike some larger algae eaters, they do not damage delicate plants and can clean even the smallest leaf surfaces. Being shy and somewhat fragile, they should be kept in groups of three or more for confidence. They adapt well to water temperatures of 22–28°C and slightly acidic to neutral water (pH 6.5–7.5). When aquarium algae is insufficient, their diet must be supplemented with blanched zucchini or sinking algae wafers. Breeding in captivity is challenging — most available specimens are wild-caught — requiring excellent water quality and an abundance of plant-based nutrition. Newly imported specimens often have compromised digestive systems, requiring special care during acclimation.

Source: Wikipedia (CC BY-SA 4.0)

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