Comprehensive Guide to Caring for Bristlenose Catfish: Care, Breeding, and Diet

The species commonly known as Bristlenose catfish ranks among the most common and most popular tropical aquarium fish found in pet stores. They’re often recognized as “those dark fish that stick to the glass and tank bottom.” While there is an albino variety, most have dark coloring and a small “mustache.” These fish remain relatively small, growing to about 10-13 cm (4-5 inches) as adults, making them a great addition to many freshwater tanks. In my experience, they are truly exceptional fish!

Basic Requirements and Introduction

In general, these catfish aren’t very demanding in terms of space since they mostly stay at the bottom or rest on large plants. As noted above, adult specimens grow to about 13 cm (approximately 5 inches), with females being smaller than males. Like many other catfish, they are social and thrive in groups, so a tank with a base of 50 x 50 cm (20 x 20 inches) can easily house up to 15 Bristlenoses. Interestingly, many aquarists find that their first tanks are already well-suited for these fish, even if they can’t tell males from females at first. Since juveniles can’t be sexed, it’s best to wait until they mature; males will develop bristles (a “mustache”) and grow larger, with more vibrant colors than females. As long as they have a good spot to lay eggs—typically a flat rock, cave, or pipe surrounded by plants - they will breed as readily as Guppies. However, it’s crucial to avoid housing other bottom dwellers like Loaches in the breeding tank, as they might eat the eggs or fry! To provide the right environment, a larger dedicated aquarium is usually a good idea, allowing Bristlenoses to breed continuously, month after month. Observing the fry clinging to rocks, caves, and glass is truly delightful. Although many aquarists think breeding Bristlenose catfish is challenging, it’s actually quite straightforward in a properly set-up tank, and your Ancistrus population can keep growing after that initial success.

This article was initially a brief guide to caring for these catfish, but we’ve expanded it to cover essential topics like proper water chemistry and temperature, which are crucial for keeping your fish healthy and happy. Many shop assistants provide misleading information, and various websites often share content that’s simply republished from other sources, leading to a confusing mix of contradictory advice. To clear things up, we’ve included as many details as possible below. Factors like water hardness, temperature, pH, carbonate hardness, and water flow are all extremely important!

What type of aquarium is best for Bristlenose catfish?

A tank with plenty of hiding spots is essential since Bristlenose catfish are shy and prefer to stay hidden during the day. Being nocturnal, these fish become more active at night. Like compatibilitymany other catfish, they typically stay hidden all day except during feeding. Adequate hiding spaces are also crucial for the survival of newborns. Suitable hiding spots include rocks, caves, driftwood, and live plants like Anubias nana or Java moss, which these fish particularly enjoy. If you’re keeping species like Acaras, Angelfish, or Gouramis in the same tank, these hiding spots become even more important. That’s because Acaras, Gouramis, or even Angelfish can become territorial and aggressive, especially towards small or newborn Bristlenose catfish. I’ve personally witnessed the danger when a hungry Gourami in my tank ate all but one of the newborns.

Whether the aquarium is tall or shallow doesn’t matter much for this species. Good aeration, however, is absolutely essential. If oxygen levels drop too low, these fish will swim to the surface to breathe. As noted below, Bristlenose catfish have a primitive lung that allows them to take in atmospheric air as compatibilitycompatibilitycompatibilitywell. However, this can be risky for smaller specimens, as they could be caught by predatory fish. Once the newborns reach a length of 2 cm (0.79 inches), they are harder for predators to consume.

What’s the ideal aquarium temperature?

Although Bristlenose catfish can survive in water as cool as 18°C (64°F), it’s best not to keep them below 21°C (70°F). For optimal health, maintain a consistent water temperature between 22-25°C (71-77°F). Seasonal changes naturally affect water temperature, with summer temperatures rising higher than in winter. These fish thrive in warmer conditions, and during summer, the temperature might exceed 28°C (82°F). When this happens, proper aeration from a filter or air pump is essential; otherwise, your Bristlenose catfish may swim to the surface to breathe. It’s a well-known fact that as water temperature increases, oxygen levels decrease.

What do Bristlenose catfish eat?

These bottom dwellers thrive on a varied diet including SERA tablets, mosquito larvae, worms, insects, daphnia, and brine shrimp. While Bristlenose catfish breed most effectively when fed live or frozen foods, they will also reproduce with a diet of SERA tablets, available in both meat and vegetable varieties. Offering a mix of high-quality foods ensures they receive essential vitamins and minerals while reducing the likelihood of widespread disease in your tank. These catfish are not picky; they’ll consume food that settles on the substrate, including flakes and even dead fish. Regular treats like mosquito larvae and worms—either live or frozen—add essential variety to their diet, as no one enjoys eating the same thing every day. Be cautious not to overfeed, as this can be fatal to your Bristlenose catfish. Want to see what happens when you add a carrot to a tank with Bristlenose catfish? They love it! Carrot is nutritious and supports both growth and overall health.

Water Hardness, pH, and Other Considerations

pH levels are crucial for the health of newborn Bristlenose catfish, but adult fish are quite resilient. Many beginners neglect to test water chemistry, yet these catfish thrive and breed well in slightly acidic water (pH around 6.5) with temperatures ranging from 22-28°C (71-82°F). General water hardness is less critical for these plecos, but it's important to maintain it within a range - no lower than 4 and no higher than 24-25. Regular weekly water changes are not necessary as long as you keep the water properly mineralized.

Naturally, we do recommend to keep aquarium, fish and plants healthy - so if you're not pro at mineralising water, you'll better perform water changes as it's simple.

For breeding Bristlenose catfish, the pH should ideally be neutral or slightly acidic, though a range between 6.5 and 7 is fine. Monitoring carbonate hardness is essential; it should be 4 or higher to ensure most fry survive. A carbonate hardness of 4 or above will keep the pH stable. If the carbonate hardness (KH) drops below 4, the pH can fluctuate significantly, ranging from 7 in the morning to as low as 5.5 by evening. To correct this, add one teaspoon of sodium bicarbonate per 100 liters (26.42 US gallons or 22.00 Imperial gallons) and test the KH again. If it remains below 4, repeat the process until the KH reaches 4 or higher.

How Many Bristlenose Catfish Can You Keep?

The number of Bristlenose catfish you can keep depends on a few factors: Are you keeping males, females, or both? Males are more territorial but can become accustomed to each other over time. Each Bristlenose catfish requires about 10 square centimeters (1.55 square inches) of space in the tank. Providing hiding places and bogwood is essential. Adding live plants to the tank is also beneficial, as they improve water quality, help define territories, and keep the fish more relaxed.

Breeding Bristlenose Catfish

To encourage Bristlenose catfish to breed, simulate rainy seasons, as these fish often breed during this time when food is abundant. For more details on how to create these conditions, click here. Bristlenose catfish prefer a breeding temperature of 24 - 26°C (75.2 - 78.8°F), but temperature alone is not the most crucial factor. The key to successful breeding is protecting the eggs. If other bottom dwellers, such as Loaches, are in the tank, make sure they cannot reach the eggs. Breeding is more successful when Bristlenose catfish are the only species in the aquarium. The female will lay eggscompatibility under driftwood, in caves, or in pipes. After fertilization, the male will guard the yellow eggs and may stay hidden for 3-4 weeks, depending on the number of females and their readiness to breed. During this period, he will fan the eggs. In my experience, breeding Bristlenose catfish is quite straightforward and requires little intervention from the aquarist.

Neither parent will consume the eggs or fry. Accurate sexing of the fish is essential for breeding, and details are provided here. A pair is ready to breed when both fish reach 7-8 cm (2.76 - 3.15 inches) in length. However, this size alone does not indicate sexual maturity, as diet also plays a role. While a diet high in protein promotes growth, it does not ensure that the fish are ready to breed. Typically, it takes 6-10 months for the fish to reach the 7-8 cm size.

How Often Do Bristlenose Catfish Breed?

Under ideal conditions, Bristlenose catfish can breed every month. However, you may observe occasional breaks in breeding, as it can be challenging for a female to produce eggs continuously.

What Should You Know Before Buying Bristlenose Catfish?

• Bristlenose catfish typically live for around 8 years. If you plan to keep your aquarium for only 1-2 years, it's better not to buy this fish.
• While Bristlenose catfish are generally peaceful, they do require their own space. Adult males may occasionally fight with each other, but these fights are not lethal. When breeding, your tank could become crowded with fish. Rather than selling or giving away the fish due to overcrowding, it's advisable to sell or rehome them when they reach adulthood or about 6 cm (2.36 inches). Adult fish are hardier in a new environment and are more valuable due to their size and appearance.
• Bristlenose catfish enjoy a variety of foods, including tablets, pellets, worms, larvae, and meat. Although some store staff might claim that these fish will consume all the algae in your tank, this is not true for adults. Newborn Bristlenose catfish, however, are avid algae eaters and will consume it throughout the day until they reach about 2-3 cm (0.79 - 1.18 inches) in length.
• Bristlenose catfish need driftwood in their tank. Not only does it help divide their territories, but it also provides a habitat for algae growth, which is important for young fish. Additionally, driftwood can enhance the fish's well-being and activity levels.

Compatibility of Bristlenose Catfish

Bristlenose catfish are generally peaceful and get along well with other calm species such as Corydoras, Angelfish, Discus, and other non-aggressive fish. However, if you plan to breed your Bristlenose catfish, it is crucial to choose tankmates that will compatibilitynot prey on their eggs. For instance, Yoyo loaches are capable of reaching and consuming the eggs, while smaller fish like Corydoras panda are not. Additionally, Ramshorn snails can pose a threat to the eggs, even though they are slow-moving and generally not regarded as dangerous by the catfish.

Video

Download the video here: link (approximately 7.3 MB, mpeg format, MPEG-1 mpeg type, 640x480px)

Pictures of Bristlenose catfish

Here below follows the photogallery added on 11/30/2006. You are allowed to use any of the pictures below on your own web site however you must place a link to aqua-fish.net in such a case. Click on any image to enlarge.

Pictures added on February 22th 2011

Questions and answers about catfish

On March 20th 2011 we added the following questions and answers here due to merging aqua-fish.net/answers with related articles. Even though the article above is dedicated to Bristlenose catfish, the following questions are about catfish in general; Including corydoras and other types of catfish. You're welcome to post your own questions too; use a form that can be found at the bottom of this page, please. Make sure that your questions are unique and yet unanswered on this page.

• Why do my catfish swim towards the top of the tank?

  Answer: Many catfish are labyrinth fish. This means that they have some form of primitive lung, a gulp of air is required every now and again.

• Why doesn’t my catfish move around the tank?

  Answer: Catfish are mostly nocturnal fish and will only become fully active once the tank lights have gone out. During the day they will normally seek out any hiding places that they can find.

• Why does my iridescent shark only swim when the lights are out?

  Answer: Iridescent sharks belong to the catfish family and as such tend to hide in bright lighting. They become more active after lights out as they are classed as nocturnal swimmers.

• What does a catfish look like?

  Answer: Each species will have different coloring and features. See these examples: Plecostomus Catfish, Bristlenose Catfish (see pictures above), Shark Catfish.

• Which nutrients do catfish need to keep healthy?

  Answer: Protein is the most important nutrient required by fish, fatty acids will provide the fish with stamina. Always check the dietary needs of your fish as all fish foods will list their ingredients and nutritional value of them.

• How can I get my catfish to spawn?

  Answer: Keep several females with one male and add plenty of suitable spawning sites to encourage them. Piping and caves will be ideal. Feed the parents with plenty of live or frozen foods to condition them.

• At what size do Bristlenose's breed?

  Answer: Usually when they’re at least 10 cm (3.94 inch) long. Non-dominant males can be ready to breed at smaller sizes, so after removing the dominant male it's possible to see an 8 cm (3.15 inch) long specimen trying to spawn with a bigger female.

• Where can I buy a bristle nose catfish?

  Answer: Your local pet store may carry these, or may be able to bring them in for you.

Video #2 and #3

Feel free to download our video showing two albino Bristlenose's fighting with each other: download the video link (the file is approximately 274.5 MB large). Another video showing feeding Bristlenose catfish: download the video by clicking here (approximately 58 MB)