Upside Down Catfish: Species Profile

Category: Catfish

Common Names: Upside Down Catfish

Scientific Name: Synodontis nigriventris

Family: Mochokidae

Minimum Tank Size: 30 Gallons

Care Level: Easy

Temperament: Peaceful

Max Size: 4 Inches

Temperature: 72-82 F

pH: 6.0-8.0

Tank Level: Bottom

Colors: Black, White

Diet: Omnivore

Breeding: Difficult

Swimming Upside Down Catfish

Upside Down Catfish Species Overview

When a fish swims upside-down, it usually indicates a serious problem. However, this interesting little fish can remain in this inverse position most of the time.

Species Overview

Upside down catfish are an excellent choice for anyone in the fish-keeping hobby, from absolute beginners to the most experienced. You don’t need a huge tank with a complicated filtration system to keep these guys healthy and happy.

This aquatic acrobat with an easy-going nature is a perfect aquarium fish that anyone can enjoy.

These cute little guys are not your average slimy, mustached river dweller that we find in North American rivers.

Synodontis nigriventris are dwarf catfish with a forked tail, three sets of barbels, a large adipose fin, and big eyes. They also have spines like most other catfish. They can easily become entangled in a coarse mesh net or injure you during handling.

Distinguishing Features

The most distinguishing feature of these little catfish is their adapted color. Fish that swim upright have a darker hue on their dorsal side and are lighter on their underbelly.

Upside down catfish are darker on their underside to help camouflage them when they swim upside-down near the water’s surface.

Their bodies are predominantly light brown with various-sized, darker brown splotches. They can also be light, almost yellow. Occasionally they have white spots.

Upside Down Catfish on Gravel


There is only one known commercial breeder of upside-down catfish in the US. They are notoriously difficult to spawn. The collection of wild fish continues for supplying the market.

Humans have observed and enjoyed upside down catfish for centuries as indicated by their presence in Ancient Egyptian paintings.

Today, they are mostly found in central Africa. Collectors find them in Malabo Pool in the Congo River Basin, in the Lekenie River, and in other tributaries of the Congo River. You can also find them in Cameroon and Kinshasa.


These cats make popular aquarium fish because they are a species of catfish that don’t get too big for a medium size tank. Adults reach about 3.5 to 4 inches in length. Females tend to have a rounder-looking body and are slightly larger than males.


There is no definitive data on how long upside down catfish live. Some sources say as little as five years, while other sources say up to fifteen. Proper care helps to extend the life of any aquarium fish.

When you maintain healthy water parameters and don’t add fish that might prey on your upside down catfish, you can expect to keep them for about ten years


There are no significant differences between the male and female upside down catfish. Females tend to be larger and lighter in color.


These guys are peaceful fish who like a school of at least three or four. They make an ideal community tank group.

Tank Parameters

Setting up a fish tank is no small endeavor. There are several variables to juggle and having a plan is necessary.

If you are new to keeping fish, expect to set up your tank several weeks before getting your fish. Since these fish are sensitive to nitrates in the water, it is particularly vital to cycle your tank before adding upside down catfish to it.

Minimum Tank Size

All fish need a minimum amount of space to grow and feel comfortable. The tank size depends on how large the fish get, how many you have, and if you have other kinds of fish in the same tank.

Usually, 5 gallons is the absolute minimum for only one fish, though you can find smaller tanks on the market.

Upside down catfish form schools, so they don’t like to be alone. They are stressed out without the comfort of other catfish. You can keep just one in a small tank, but it won’t be optimal living for that fish.

The next factor to consider is the adult size. These cats are small fish that reach about 3.5 to 4 inches long as adults. It may seem like a waste when you have babies in a 20-30 gallons tank, but as they grow up, you’ll be glad you are prepared to have enough room for everyone.

You can keep three or four fish in a 10-gallon tank. The ideal group size for these catfish is 4 to 6. For that, you’ll want to consider a 20-gallon tank.

Last, consider if you want to make this a community tank in the future. If you think you might like to add other types of fish later, a 30-gallon tank or more would be in order. If you go for the large tank and don’t make it a community later, your upside down catfish will enjoy all the lovely space they have to themselves.

Water Parameters

As with any fish-keeping endeavor, research online will yield various opinions about water parameters and tank size. Luckily, upside down catfish are hardy little fish that are easy to care for. They have a broad temperature and pH tolerance.

You can monitor water parameters with test strips or test kits available at your local fish store or pet store.


Fish are always happiest when you simulate their natural environment in their tank. Similar to their native African rivers, 72-82° F (24-28° C) is the tolerable range for water temperature.

A note to beginners: just because a fish can tolerate a wide range of temperatures doesn’t mean that letting the water fluctuate widely is good for them. Do your best to keep a tighter range. The optimum for upside down catfish seems to be 75-79° F.


Like temperature, wide fluctuations in pH are not good, even if the fish can tolerate a broad range. These catfish prefer slightly acidic to slightly alkaline water with a pH of 6 to 7.5. It doesn’t sound like a broad range, but in terms of pH, it is.

On the pH scale, 0-6.9 is acidic, 7 is neutral (pure water), and 7.1-14 is alkaline.

You must regularly test the pH level in all your fish tanks to keep them balanced. Sudden algae bloom can indicate water has become too acidic or too alkaline. Fish tend to exhibit rapid, chaotic swimming patterns in alkaline water.

Your tank’s pH can drop too low when there are too many fish, the substrate is hiding waste material, or there are not enough plants.

Regular water changes help to keep your pH in balance, too.


One thing that makes upside down catfish easy to care for is that they are freshwater, tropical fish. While you’ll need to have moderately warm water with low pH and nitrates, you won’t need to reproduce a delicate level of salinity for these fish.

  • Temperature 72-82° F
  • pH 6-7.5
  • Salinity 0

Upside Down Catfish on Sand next to Driftwood

Tank Setup

Since these fish originated in river waters with dense vegetation, a tank setup reflecting that environment will make your upside down catfish feel right at home.


A substrate of fine sand is best for these fish for several reasons. While upside down catfish prefer to feed on the surface of the water, in aquarium life, they often feed on the bottom of the tank as well.

A rocky substrate can harm their barbels. Cuts and bruises on their barbels are certainly a source of disease in a natural setting. You can help avoid that in your aquarium.

They thrive best in a heavily planted tank with broad-leafed foliage to hide in and feed on. Live plants are preferable to artificial so a thick, sandy substrate is ideal for all the plants you’ll want to include in their aquarium.


Part of the fun of keeping an aquarium is making it look amazing. Your setup can be a focal point in your home and a conversation starter for all your guests. The goal is to balance aesthetics with your fish’s needs.

Upside down catfish are native river dwellers. Rock arches, driftwood, and rocks help simulate their natural habitat.

These catfish are peaceful and bashful by nature. Places to hide are another essential element to consider at you decorate your tank.


Upside down catfish prefer a well-planted tank with lots of hiding places large enough to accommodate the whole school. They love to hang out on the underside of broad-leaf plants,

Some broad-leaf plants are Anubias Barteri, Ludwigia, and Sagittaria.

Floating plants like amazon frogbit and water lettuce are enjoyable for them as well. They browse the underside of the roots while swimming upside-down.


Like most other catfish, these are more active at dusk and during the night. You can use a moonlight lighting fixture to see them during their active hours.

Daytime lighting depends on the size and set-up of your tank. If you have live plants, you’ll need lights that simulate natural sunlight for photosynthesis.


Upside down catfish are sensitive to nitrates, so keeping your water conditions good is vital to keep them healthy. You’ll need to do partial water changes fairly frequently.

Most fish respond to high nitrates with swim bladder problems. Finding them floating sideways or upside-down clues you into potential issues. Since you won’t get that signal with these fish, you’ll have to keep a close eye on your nitrates by testing your tank water.

Upside down catfish like a strong current and highly oxygenated water. A spray bar or power head hooked up to a canister filter is an excellent system for achieving both ends.


Temperature is not a vital parameter for these fish. Many freshwater, tropical fish like a balmy 72-79° F. If they have tank mates who have a stringent temperature tolerance, you can set the water temperature for those fish, and your upside down catfish will be just fine.

Otherwise, a basic heater will work well for these fish. Just make sure that it is large enough for the tank.


You won’t be surprised to find that these catfish feed off the underside of submerged plants and branches. Swimming upside-down makes this activity easy.

Their first choice of food is insects on the surface of the water, though they will graze on algae if it is available.

As both top and bottom feeders, you can give them high-quality tropical fish flakes or sinking catfish pellets to keep them healthy and happy. You may find them enjoying some algae in your tank as well.

A varied diet is the best way to keep your fish in optimal health. Frozen or freeze-dried bloodworms, insect larvae, shelled peas, and cucumbers add a pleasant variety to their typical routine.


These fish are cave-breeders, making it difficult to spawn in an aquarium setting. There are a few things you can do to set the mood.

Use a couple of clay flower pots or a length of PVC to mimic a cave setting.

Soften the water slightly and add colder water with a watering can. As you simulate the spring rains, it may stimulate the fish to breed. Providing live food helps to condition them for breeding also.

The whole process takes about fifty days. Separate a breeding pair in a larger tank set up for spawning and leave them alone for at least six weeks.

The female can lay up to 450 eggs on the cave roof. Mom and dad will tend the brood so you can leave the male in the same tank.

The eggs hatch about two or three days after the female lays them. The fry can feed on their yolk sacs for about four more days. After that, fresh brine shrimp are an excellent food for them.

At first, the fry will swim upright. Don’t worry, there is nothing wrong with them. They will flip and spend most of their time swimming upside-down after about two months.

Neale Monks [CC-BY-SA-3.0]

Common Diseases

Upside down catfish are easy to care for fish that are great for beginner aquarists. They don’t suffer from any species-specific diseases. However, every fish keeper eventually runs into a few common ailments.


Ick is a common fish disease associated with alkalosis. This happens when the pH in your tank is too high. If your fish are swimming chaotically, have their gills spread wide, and have mucus on their gills, they may be suffering from ick.

You may observe tiny white spots all over their bodies. They will often try to scratch themselves on rock and driftwood features in the tank.

Treating Ick

You’ll need a three-pronged approach to treating Ick. You’ll work to balance the pH and raise the temperature while treating the fish with medication. The process may take several weeks.

A rapid change in pH is just as harmful as the result of letting your water become too alkaline. Use an over-the-counter product from your local fish store to change the pH by about three units each day. Be sure to follow the label carefully.

Ich comes from an opportunistic protozoan (Ichthyophthirius multifiliis) present in the water. It attacks the fish in stressful situations such as alkalosis. Raise the water temperature to 80° F over a few days. This will kill the Ich organism.

Bacterial Infections

Earlier we talked about the dangers of barbel injuries for catfish. If your upside down catfish get this kind of injury, they are then susceptible to a bacterial infection. There are several bacteria common to aquarium fish, but you would treat most of them the same way.

Treating Bacterial Infections

Prevention is the best medicine, of course. Keeping your water parameters within optimal range and keeping the tank clean are the best ways to prevent opportunistic bacteria from infecting your fish.

Beginners, be advised that adding new fish to an aquarium introduces potentially new bacteria to all your fish. Having a “quarantine” tank for new or sick fish is a common practice for keeping all your fish healthy.

If you do have a sick and injured fish, you can treat just that fish or the whole tank. Typically, you won’t want to use an antibiotic on fish who are not sick. That’s where your quarantine tank comes in.

Signs of bacterial infection are dark spots on the tips of fins or barbels, lethargy, and not eating.

Make sure your quarantine tank has the right water parameters. Move the infected fish into it. Treat your fish there until they are healthy enough to rejoin the community tank.

Potential Tank Mates

These peaceful catfish make excellent community tank members with a few caveats. While they are not aggressive, they are omnivorous. They may feed on other tiny fish in a community tank.

Although, they will remain shy and hide much of the time unless they have a school size of at least three or four.

Other larger fish that may try to each your upsidedown catfish are not well-suited tank mates either. They will stick out their spines if another fish tries to eat them and lodge in the predator’s throat.

Non-aggressive, similar-size fish like African tetras, dwarf cichlids, and other catfish like corydoras make the best tank mates for your upside down catfish.