Corydoras vs Otocinclus
Both are peaceful, group-loving little catfish, but they do very different jobs. The bronze corydoras is a hardy bottom scavenger; the otocinclus is a tiny, sensitive algae grazer. Here's which one your tank actually needs.
The quick verdict
If you want a hardy, active bottom-cleaner that sifts up leftover food and copes with a young tank, choose the bronze corydoras. If you have a mature, algae-friendly tank and want algae grazed off glass and leaves, choose the otocinclus — just know it's more delicate. Many community tanks keep both.
| Bronze corydoras | Otocinclus | |
|---|---|---|
| Care level | Easy | Intermediate |
| Job in the tank | Bottom scavenger | Algae grazer |
| Min tank size | 75 L / 20 gal | 40 L / 10 gal |
| Adult size | 6–7 cm | 3.5–4.5 cm |
| Hardiness | Very hardy | Sensitive, needs mature tank |
| Diet | Omnivore (sinking foods) | Herbivore (algae/biofilm) |
| Group size | 6+ | 6+ |
| Best for | Beginners, tidy substrate | Algae control in planted tanks |
Scavenger vs grazer
The bronze corydoras is a robust, endlessly busy bottom-dweller that snuffles through soft sand for sinking food and detritus. It's hardy, forgiving and one of the best beginner catfish — though it doesn't touch algae, so don't buy it as a clean-up-crew for green glass. The otocinclus is the opposite: a tiny, dedicated algae grazer that keeps leaves and glass clean, but it needs an established tank with a steady biofilm supply and struggles in new setups. Feed otos supplementary algae wafers and blanched veg when natural algae runs low.
Which should you keep?
Our pick
Pick the bronze corydoras for a hardy, entertaining bottom crew in almost any community tank, especially a newer one. Pick the otocinclus if you specifically need algae grazed and your tank is mature and stable. Read the full bronze corydoras care guide and otocinclus care guide, or browse aquarium setups.
Frequently asked questions
Do corydoras or otocinclus eat algae?
Otocinclus are the algae eaters — they graze soft green and brown algae off glass, leaves and hardscape all day. Corydoras are not algae eaters; they are bottom-scavenging catfish that sift the substrate for leftover food and detritus. If you want algae grazed, choose otos; if you want the bottom kept tidy of uneaten food, choose corys.
Are otocinclus harder to keep than corydoras?
Yes. Bronze corydoras are hardy and adaptable, making them a great beginner catfish. Otocinclus are sensitive: they need a mature, established tank with a steady supply of soft algae and biofilm, and they often arrive weak from shipping. Get otos only for a settled, algae-friendly tank, not a brand-new one.
Can I keep corydoras and otocinclus together?
Yes, they make excellent tankmates. Both are peaceful, both prefer to be in groups of six or more, and they occupy slightly different niches — otos graze algae on surfaces while corys work the substrate. Their water parameters overlap well, so a planted community tank suits both.
Found your model? Buy it at the right price.
UniverTrack tracks the real price of your aquarium gear across several retailers, spots fake discounts and warns you when it's genuinely the right moment to buy — with an AI assistant to guide you.