Sterbai cory is popular among freshwater aquarists due to its peaceful and schooling nature. Moreover, it is also one of the most inexpensive corydoras.
They are super low maintenance and yet extremely intriguing. Whether you’re a pro or an amateur, no aquarist can ever go wrong with this uniquely colored fish.
Keep reading if you can’t wait to know more about these tiny-little fellows!
Species Overview
| Origin | Guapore River between Central Brazil and Bolivia, South America |
| Order | Siluriformes |
| Family | Callychthyidae |
| Scientific Name | Corydoras sterbai |
| Common Names | Sterbai cory, sterba’s cory |
| IUCN Red List Status | Not Evaluated |
| Appearance | Mostly brown to black body with white spots. Its mouth is on its bottom side. |
| Size | Up to 5.0 cm |
| Lifespan | Up to 10-15 years |
| Temperament | Peaceful |
| Tank Level | Bottom dwellers |
| Water Temperature | 78-82 °F (25-27 °C) |
| pH Level | 5.8-7.0 |
| Water Hardness | 2-12 dGH |
| Care Level | Easy |
| Minimum Tank Size | 30 gallons for 6-8 fish |
| Tank Environment | Spacious tank with shade, hiding spaces, and oxygen-rich water |
| Diet | Omnivorous with scavenging nature |
| Tank Mates | 5-7 other sterba’s corys and quiet tankmates |
Natural Habitat
Naturally, the fish is found in regions of the Guapore River between Brazil and Bolivia, South America. It is also found in small tributaries of this river with swift-flowing water with sparse vegetation.
The fish prefers to inhabit acidic and soft water with low levels of nitrates and nitrites. It stays close to the dark and shaded riverbed. This helps this shy species hide and remain active with the entire shoal.
Classification
This fish belongs to the Callychthyidae family under the order Siluriformes. It is scientifically known as Corydoras sterbai. It was first discovered in 1962 in South America by Dr. Gunther Sterba.
Commonly, it is popular as sterbai cory and sterba’s corydoras.
Fun Fact: The fish is diurnal, but it becomes more active after dusk. So, make sure to feed them once in the evening to replenish their energy.
Appearance
Sterbai cory is often confused with mosaic cory. However, to recognize this species properly, you must know it in more detail.
Size
The adult male fish is about 5.0 cm (1.96 in) long. The adult female fish is a bit longer.
Color
The base body color is brown to black, with white spots all over the dark space. The fish is also available in albino and black species. The fins are also similarly colored and patterned but are transparent. But the white dots are more like dashed stripes.
Features
It has a short and thick body shape and a rounded head. Its mouth is towards the bottom side and has multiple barbels to scavenge leftover food efficiently.
On both sides of the body, the fish has two rows of armor made of scales. This feature protects it from predators.
Its eyes can move around pretty fast. So, if you stare at it for a long time, you may feel it winked at you.
Sexual Dimorphism
You can easily tell apart the male and female fish if they are housed together and seen from the top of the tank. The female fish is rounder than the male and a little longer. This is especially prominent during the breeding season.
Behavior & Temperament
The sterbai cory catfish is extremely sociable with its species but shy around others. It prefers to live in groups to confidently swim in the tank. It rather feels intimidated around hyperactive fish.
Lifespan
With the best maintenance, like water conditions, diet, and company, the fish can live until 10 to 15 years. But negligence can considerately shortens its lifespan to 7 years.
Author’s Note: In my experience, sustaining them for 20 years is possible only if you care diligently. It’s better to invest in a quality-grade water parameter testing kit.
Sterbai Corydoras Care
To sustain the fish to its maximum lifespan, you must know the details about their preferred living environment as listed below.
Tank Size
To house about the minimum sterbai corys, i.e., 6-8, you need at least a 30-gallon tank.
Water Chemistry
Since it is a freshwater fish, you must comply with the following requirements.
- pH Levels: 5.8-7.5
- Water Temperature: 72-88 °F (22-31 °C)
- Water Hardness: 2-12 dGH
- Ammonia: 0 ppm
- Nitrite: 0 ppm
- Nitrate: 0 ppm
Tank Environment
You can also sustain sterbai corys for longer with a living environment that mimics their original habitat. So, read on to set up your tank perfectly.
Substrate
Choosing a high-quality, smooth substrate like fine sand would be best. Otherwise, go for the smoothest gravel available. This will protect your cory’s barbels from getting injured. Avoid pebbles as they are too tough.
Plants
The fish doesn’t harm plants, so you may add a few of them. You can also add dry leaves and peat moss to add tannins and maintain the pH and water hardness.
Lighting
It thrives more in dim lighting.
Décor
Since the fish doesn’t appreciate bright lighting, add caves and driftwood as hiding spaces for it.
Filtration
Use a robust filter to clear all toxins and keep your pet fish healthy.
Water Flow Rate
Invest in a pump or filter with high power to mimic the water flow rate of its Amazonian habitat.
Fish Care Tip: If you stain the water with tannins, make sure to change the water regularly to avoid pollution. Don’t let any plant matter rot in the tank.
Food & Diet
The fish is omnivorous, so it enjoys a range of feeds like insects, invertebrates, live food, flakes, frozen sinking feed, micro pellet feed, and prepared feed. You can also feed it fresh vegetables like zucchini.
But, live and frozen food like mosquito larvae, daphnia, and bloodworm should be fed only once weekly due to their high protein content.
Since it is a bottom feeder, it will clean any food left by other tankmates. However, it isn’t keen on feeding on algae. It also thrives on small crustaceans, plant matter, and worms.
Notice if other tank mates eat their food. In that case, place the food in hidden areas like caves.
Tank Mates
Firstly, it is a schooling (grouping) fish, so it needs 5-7 of its own kind. Otherwise, it may get sick from being lonely and intimidated by other tankmates.
Besides that, it is mostly compatible with other cory catfish and small fish, which is equally peaceful and calm. For instance, you can get the following:
- Betta fish
- Danios
- Gouramis
- Similar-sized tetras
- Barbs
- Apistrogramma
- Loaches
- Guppies
- Minnows
Tank Mates to Avoid
While getting tank mates, you must avoid any fish that’s aggressive, lively, colorful, too big, or gluttonous. Some of them are:
- Bronze catfish (though they are corys, they don’t school with sterbais)
- Texas cichlids
- Oscars
- Mollies
- Ancistrus
- Jack Dempsey
You must also avoid other bottom to middle-dwelling species. Otherwise, your pet fish won’t have ample space to swim or hide.
Common Diseases
Sterba cory is pretty sensitive to water conditions. So, keep an eye out for these possible diseases.
| Disease Name | Causes | Symptoms | Treatment |
|---|---|---|---|
| Ich | Protozoan parasite | White raised spots, lesser and slower activity, poor appetite | Temperature elevation, ich medication, aquarium salt |
| Fin Rot | Bacterial infection | Fraying or disintegrating fins, discolored fins or red streaks on fins, lesser and slower activity, poor appetite | Water parameter elevation, removing physical injury sources, antibiotics |
| Columnaris | Bacterial infection | White to grey patches, fin fraying, lesser and slower activity, poor appetite | Antibiotics, water condition improvement, stress reduction |
| Nitrite poisoning | Excess nitrite and nitrate concentration in water | Swimming slower than shoal, swimming in top layer of tank, being stagnant on tank bottom, breathing fast, not eating | 30% water volume replacement, feeding lesser to avoid nitrite pollution from leftover food |
| Red blotch disease | Bacterial infection, environmental stress. lack of space and oxygen in the water | Red sores on and around the belly | Medication (Seachem KanaPlex, API furan 2) Can be prevented; put them in a spacious container with oxygen-rich water during shipping |
Important points to keep in mind:
- Since the fish is salt sensitive, add only a small amount of salt to treat ich if the tank is more than 20 gallons. Otherwise, avoid it altogether.
- Your pet fish may also suffer from barbel damage. Prevent it by using antibacterial medicines, as nothing can make them regrow barbels.
- Don’t let them get stressed or they may release chemicals that can make them and other tank mates sick or kill them.
Breeding & Reproduction
This fish is the easiest to breed among all corydoras. All you need to do is keep two males for each female (all of age 3 to 4 years minimum) in your tank. It is better to keep an older female for higher chances of successful breeding.
Maintain a healthy diet and regularly change at least 50% of the water with colder and cleaner water. This also maintains low pH, around 6.0, and keeps the water soft.
Drop the temperature by 2-3 degrees (until 75 °F)to mimic the Amazonian waters of the rainy season.
Mating Ritual
The males court the female by rubbing their barbels until she feels ready to mate. Both fish join to form the T-position, and the male fish passes his semen into the mouth of the female fish.
The female fish uses the semen to fertilize ten of her eggs at once and deposits them in a safe space. This is usually the aquarium glass where freshwater flow is available. She may lay up to 100 eggs or more, but not all get fertilized.
Development
The eggs hatch after 72-96 hours and eat their egg sac for nutrition. Since the sterbas don’t protect their fries, house the adult fish in a separate tank.
Keep a thin sand layer and plenty of hiding spaces in the tank for fries. Feed the fries fry-friendly pellets, finely chopped feed, brine shrimp, and infusoria.
Breeding Tip: Use a small box-type or air-powered sponge filter in the tank with fries to avoid getting them sucked into the pump.
Quick Buying Tips
Most sterbai corys available commercially are farmed in various other regions worldwide. The captive-bred ones are more hardy and sustainable than the wild-bred ones.
If a seller claims explicitly about selling wild-bred fish, but their store is not near the Guapore River region and has regular shipping charges like others, they might be insincere.
A word from FIA
With a dedicated tank for sterbai corys alone, you will never have to worry about them getting hurt. They also add serenity to your tank with their in-sync swimming.
And if you’re satisfied with all the information, don’t forget to share this article with your cory-lover buddies. For queries, you can drop us a mail; we promise to reply as soon as possible!