Corydoras Care Guide — The Best Tank Cleaners

Corydoras catfish — 'cory cats' — are one of the most beloved fish in the hobby. They're peaceful, social, efficient scavengers, and have hilarious personalities. They'll dart to the surface for air, waggle their barbels while searching for food, and even appear to 'play' with each other. No community tank is complete without them.

Why cories need groups

Cories are highly social schooling fish. A lone cory is a stressed cory — it will hide, eat poorly, and its lifespan decreases dramatically. Keep a minimum of 6 of the same species. They shoal, sleep in piles, and forage together. A group of 10 bronze cories is one of the most active and entertaining sights in fishkeeping.

Substrate: soft is essential

Cories dig and root through substrate with their sensitive barbels — the whisker-like appendages on their face. Sharp gravel damages barbels, leading to infection and loss. Always use fine sand or smooth, small-grained gravel for cory tanks. Pool filter sand is cheap and perfect. Check barbels weekly — healthy barbels are long and intact.

Popular corydoras species

Bronze cory (C. aeneus): most common, very hardy, perfect beginner cory. Panda cory (C. panda): black-and-white markings, slightly smaller, extremely popular. Emerald cory (Brochis splendens): larger, brilliant green color, very active. Pygmy cory (C. pygmaeus): tiny (1 inch), perfect for nano tanks, true midwater schooler. Sterbai cory (C. sterbai): spotted, tolerates higher temperatures — works with discus.