The bright colors and flowing fins of betta fish make them a popular choice for small home aquariums. At the same time, armored bottom dwellers like corydoras catfish help clean the tank while adding interesting behavior.
But can these two very different fish live together happily in a limited 5 gallon space?
If you’re short on time, here’s the quick answer: yes, you can keep a single male betta with a small group of pygmy cory catfish or one to three other small cory species in a heavily planted 5 gallon tank.
Success depends on selecting compatible tankmates, providing plenty of hiding spots, and keeping up with tank maintenance to prevent aggression over territory disputes.
Tank Requirements
Tank Size
A standard 5 gallon tank is generally considered the bare minimum size to house a single betta fish. However, adding cory catfish to the mix requires more horizontal swimming space. Ideally, a 10-15 gallon tank is recommended for keeping these two species together.
Water Parameters
Bettas prefer warm water between 78-80°F, while cory catfish do best in slightly cooler temperatures of 72-79°F. Aim for the overlap at 78°F. The pH should be between 6.8-7.5 and hardness between 5-12 dGH. Frequent partial water changes are important to maintain high water quality.
Tank Setup and Decorations
The tank should have a gentle filter, lots of hiding spots, and a soft sandy substrate. Add plants like Java fern and Anubias along with driftwood and rock caves. These create sight barriers to reduce aggression between the betta and cory cats.
A darkened substrate also makes the pale cory cats feel more secure.
Tank Filtration
A gentle hang-on-back or sponge filter is perfect, providing a low flow rate. The water should turnover at least 5 times per hour. Ensure the intake is covered with a sponge to prevent the corys’ fins from getting sucked in.
Additional air stones help oxygenate the tank, which is important for the catfish who are more sensitive than bettas.
Tank Maintenance
Test water parameters weekly and aim for 0 ammonia, 0 nitrites, and < 10ppm nitrates. Change out 25% of the water 1-2 times per week, vacuuming the substrate to remove waste. Wipe down tank walls to prevent algae overgrowth and ensure the filter media stays clean.
With proper tank maintenance, this setup can thrive!
Selecting Compatible Cory and Betta Species
Betta Splendens
The common Betta Splendens, also known as Siamese Fighting Fish, are one of the most popular choices to pair with Corydoras catfish. Male bettas are aggressive toward each other, but do well with most community tank mates. Females can be kept together in small groups.
Both males and females thrive in 5 gallon tanks when parameters are stable.
Pygmy Corydoras
Pygmy Corys, including Corydoras pygmaeus, C. hastatus, and C. habrosus, are excellent options for 5 gallon aquariums. These tiny catfish reach less than 1 inch in length when fully grown. They are peaceful, shoaling fish that spend most of their time scavenging along the bottom.
A group of 6 pygmy cories brings movement and activity without overwhelming a small tank.
Other Small Cory Species
In addition to pygmy varieties, several other Cory species stay under 2 inches and can live in a 5 gallon tank. Good choices include:
- Corydoras panda – A popular black and white catfish that grows to 1.5 inches.
- Corydoras habrosus – The salt and pepper cory reaches 1.5 inches in length.
- Corydoras trilineatus – Grows to 2 inches and has three dark stripes running the length of its body.
Avoid These Cory Varieties
Some Cory catfish get too large for a 5 gallon tank. Avoid the following:
- Corydoras sterbai – Grows over 2 inches in length.
- Corydoras aeneus – Can reach 3 inches when full grown.
- Corydoras metae – Reaches 2.5 inches in size.
Selecting small, peaceful Corydoras and Betta species allows both fish to thrive in a heavily planted 5 gallon aquarium. Proper filtration, heating, water changes, and tank maintenance are also crucial for their health and happiness.
Adding Fish and Observing Behavior
Acclimating New Tankmates
When introducing new fish like Cory catfish to an established betta tank, it’s crucial to acclimate them slowly to prevent stress. Start by floating their bag in the tank for 15-30 minutes to equalize temperatures. Next, add small amounts of tank water to the bag periodically over 30-60 minutes.
Finally, release the Cory catfish into the tank. Turn off the lights and let the fish establish territories overnight before reintroducing the betta.
Feeding can also help ease tensions when adding new tankmates. Dropping a few flakes of food near the bottom for the Cory catfish first, followed by pellets higher up for the betta, shows each species the other’s feeding area. This reduces chances of conflict over food.
Continue supervised feedings for several days post-introduction.
Signs of Stress and Aggression
It’s normal to see some initial chasing or nipping when combining fish like bettas and Cory catfish. But continued bullying or hiding indicates a true territorial dispute. Watch for these signs of stress:
- Loss of color or frayed fins on betta
- Rapid gill movement or erratic swimming in Cory catfish
- One fish restricting another’s movement
- One fish hiding frequently, especially near tank edges
If stress signs persist beyond 2-3 days, it’s best to separate the fish. Be prepared with an extra small tank or floating breeding box just in case. Playing it safe protects both fish.
Making Adjustments
Providing more plants and decor helps define territories when blending bettas and Cory catfish. Target 6-8 hiding spots at minimum by adding leaf hammocks, cave decor, and dense plant beds like anarchis or java moss. More broken sight lines prevent bullying.
Also ensure the 5 gallon environment meets both species’ needs. Bettas prefer calmer water, while Cory catfish are active bottom dwellers. Strategically position the filter outlet to create gentle flow for the betta above while allowing stronger current near the substrate for the catfish.
Water parameters should also fall within the overlap of their preferred ranges:
| Parameter | Betta | Cory Catfish |
| Temperature | 75-82°F | 72-79°F |
| pH | 6.5-8.0 | 6.5-7.5 |
| Hardness | 5-35 dGH | 2-25 dGH |
With some strategic tank preparation and a watchful eye, Cory catfish and bettas can make engaging tankmates. But have a backup plan ready in a small tank, just in case. For more tips, see The Spruce Pets.
Feeding Both Species Properly
Betta Diet
Bettas are carnivorous fish that thrive on a diet of insect larvae, brine shrimp, bloodworms, and daphnia in the wild. In captivity, they should be fed a varied diet of high-quality betta pellets or flakes as their staple food.
Pellets and flakes provide balanced nutrition with protein, fats, vitamins and minerals. Bettas have small stomachs so feed just enough food that they can consume in 2-3 minutes, 1-2 times per day. Supplement their diet with freeze-dried or frozen foods like brine shrimp, daphnia or bloodworms for variety a few times per week.
Avoid overfeeding bettas, as uneaten food will foul the water. Bettas are prone to obesity and constipation on rich diets, so it’s important to monitor their food intake. Make sure any uneaten food is removed promptly. Fasting bettas for 1 day per week can also help prevent digestive issues.
Cory Catfish Diet
Cory catfish are omnivorous bottom feeders that forage on plant matter, insects, worms, and crustaceans in the wild. Like bettas, they thrive on a varied diet in the aquarium. A good staple food is sinking pellets or wafers that contain plant and animal matter.
Supplement their diet with live or frozen foods like brine shrimp, daphnia, and bloodworms. Vegetables like zucchini slices, shelled peas, and blanched spinach can also be offered.
Feed cory catfish small portions several times per day. Only feed as much as they can consume within 2-3 minutes. Uneaten food will decay and foul the tank water. Since cory catfish sift through substrate for food, use sinking pellets or wafers rather than flakes which bettas prefer.
Preventing Overfeeding
When housing bettas and cory catfish together, it’s essential to prevent overfeeding to maintain good water quality. Only feed what they can consume right away, and remove any uneaten food promptly. Here are some tips to prevent overfeeding:
- Observe their feeding habits and appetite to gauge appropriate portion sizes.
- Feed them separately if needed – bettas at the surface, cory catfish at the bottom.
- Use sinking foods for catfish vs floating/slow sinking for bettas.
- Feed them smaller meals spaced throughout the day.
- Vary their diet and fast 1 day per week to support digestion.
- Test water regularly and perform partial water changes to remove waste buildup.
With proper feeding techniques and portions, both species can thrive in a healthy, stable aquarium environment.
Tank Maintenance Tips
Water Changes
Performing regular water changes is crucial for keeping your 5 gallon betta and cory community tank healthy. Water changes help replenish minerals and nutrients in the water, while removing harmful compounds like ammonia, nitrites, and nitrates that build up from fish waste and decomposing food particles.
Experts typically recommend changing around 25% of the water 1-2 times per week for a 5 gallon tank with a light bio load.
When doing a water change, use a gravel vacuum to suck up debris from the substrate while removing water. Replace the removed water with dechlorinated tap water that is the same temperature as the tank water to avoid shocking your fish.
Use water conditioner that neutralizes chlorine and heavy metals in tap water for a safe water change.
Gravel Vacuuming
You should incorporate weekly gravel vacuuming into your regular water change routine. This helps get rid of organic waste that collects in the substrate which can pollute the water and become hazardous to your fish. Focus on vacuuming areas where debris tends to accumulate the most.
Take care not to vacuum up your corydoras catfish which may be sifting through the gravel looking for food. Slowly pass the gravel cleaner over the substrate to give the cories time to swim away if needed.
Small, frequent water changes are ideal rather than large, sporadic ones which can drastically impact your tank’s nitrogen cycle.
Testing Water Parameters
Use a freshwater aquarium test kit to check levels of ammonia, nitrite, nitrate, and pH once a week or every two weeks. This allows you to closely monitor water quality and catch any rising toxicity before it harms your fish. Recommended safe levels are:
- Ammonia – 0 ppm
- Nitrite – 0 ppm
- Nitrate – < 40 ppm
- pH – 6.5-7.5
Quickly address any parameters outside the ideal range by performing an extra water change and retesting. This helps provide your betta splendens and corydoras catfish with excellent water conditions.
Conclusion
While it can be done successfully, keeping a betta together with cory catfish in a small 5 gallon tank does require some extra planning and work. Carefully selecting tankmates, providing plenty of plants and hides, and staying on top of maintenance are key to creating a thriving community aquarium.
With some effort, a 5 gallon planted tank can be an ideal home that allows both a betta and cory shoal to exhibit their natural behaviors. The result can be an interesting, active little ecosystem to enjoy.
