Walk into any fish shop in Malaysia, and you will see a tank full of cute, whiskered fish wiggling on the bottom. The shopkeeper might tell you: “This is a cleaner fish. Buy one. It will eat the poop.”
Please, do not listen to that advice.
The Corydoras Catfish (“Cory”) is not a vacuum cleaner. It does not eat poop. It is arguably the most adorable, peaceful, and entertaining fish in the hobby—but only if you treat it like a pet, not a tool.
Here is the truth about keeping the “Puppies of the Aquarium.”
1. The “Lonely Cory” Tragedy
The biggest mistake beginners make is buying just one.
Corydoras are highly social schooling fish. In the wild (South American rivers), they live in groups of hundreds. They rely on the group for safety.
- The Problem: If you keep one Cory alone, it will be terrified. It will hide in the corner, stop eating, and eventually die of stress.
- The Fix: You need a minimum of 6 Corydoras.
- The Reward: When you have a group, their behavior changes completely. They will swim together, “cuddle” on the sand, and wink at you (yes, they can actually blink their eyes!).
2. The “Mustache” Rule (Why You Need Sand)
Look closely at a Cory’s face. They have delicate whiskers called barbels. They use these to dig through the riverbed looking for worms.
- The Danger of Gravel: If you use sharp, coarse aquarium gravel, it acts like sandpaper. It will wear down and cut their barbels. Once the barbels are gone, the fish cannot find food and often gets a fungal infection.
- The Solution: You must use fine sand.
- Malaysian Tip: You don’t need expensive “Aquarium Soil.” Just go to the hardware store or LFS and buy “River Sand” (Pasir Sungai). It’s cheap, natural, and soft enough for their bellies.
3. They Don’t Eat Poop
I cannot stress this enough: No fish eats poop.
Corydoras are scavengers, meaning they eat uneaten food that falls to the bottom. But they often cannot survive just on “scraps” from the Tetras above.
- Feed Them: You need to buy Sinking Wafers (like Hikari Sinking Wafers). Drop them in after the lights go out so the Corys can feast without the other fish stealing their dinner.
4. Choosing the Right Cory for Malaysia
There are hundreds of types. Here are the 3 most common ones in our shops:
- Bronze/Albino Cory: The tank-busting tank. Very cheap (RM3-RM5). Indestructible. Good for beginners.
- Panda Cory: Cute (looks like a Panda), but surprisingly sensitive. They prefer cooler water and often die in hot Malaysian tanks unless you have a fan.
- Sterbai Cory: The “Heat Proof” Cory. They have orange fins and white spots. They love warm water (up to 30°C), making them the perfect tank mate for Discus or warm community tanks.
A group of Corydoras wiggling across the sand is one of the most relaxing sights in the hobby. They are peaceful, they never fight, and they keep the bottom of your tank looking lively.
Just remember: Buy them friends (6+), give them sand, and feed them well. They will pay you back with cuteness.
