Can Bristlenose Plecos and Betta Fish be good tank mates?

Betta fish are beautiful long-finned fish. They are known for being territorial, somewhat aggressive, and slow swimmers. They are not called Siamese Fighting Fish for nothing!  Male bettas are usually fine by themselves, while female bettas can live in a sorority. But if you are thinking about adding your betta to a community tank, it is possible! As long as you choose the right tank mate.

So, can bristlenose plecos be a good tank mate for a betta fish?

Yes, they can be good tank mates for bettas!

Bristlenose plecos are calm and peaceful bottom-dwellers that will do fine with a betta, which is a mid-up-dweller. They can eat algae, thus controlling algae bloom, and most of the time, they are doing their own things. So, the chances of your betta noticing britlenoses plecos and getting aggressive towards them are very few.

When considering keeping both species under the same environment, it is important to consider a few factors such as their temperament, the number of fishes in the tank, the volume and height of the aquarium, water temperature, and pH, light availability, and finally, hiding spots.

In this post, we will talk about bristlenose plecos, their appearance, behavior, diet, breeding, tank requirements, and why they are good tank mates to your betta.

Bristlenose plecos overview

Bristlenose plecos (Ancistrus cirrhosus) belong to the Loricariidae family. They live in streams and tributaries in the Amazon basin, but they can also be found in other parts of South America and all the way to Panama. They are also known as the Bushy Nose Pleco or Bristlenose Catfish. These fish can live at least five years. But do not get surprised if bristlenose plecos live longer. There are accounts that these fish have lived up to 12 years in captivity. Talk about longevity!

Bristlenose plecos appearance

Bristlenose plecos are catfish that have evolved to have thick defensive plates that cover their bodies instead of having scales. These plates can limit their movement but at the same time, they also protect them from predators’ attacks.

As the name says, they have long bristles that usually grow higher up on the head in males. In females, the bristles are smaller and located in the mouth area. Bristlenose plecos have suckermouths on the bottom of their bodies that latch onto surfaces to eat algae, biofilm, and detritus. 

Bristlenose plecos have a fleshy, short, and wide head. They also have singular color patterns that mimic the substrate of the Amazon Basin with a mix of black, dark brown, gray, and olive with a series of lighter white and yellow dots along the body. These fish have a pair of pectoral fins, a pair of abdominal fins, and a larger dorsal fin up top. Here are some variations within the bristlenose plecos:

  • Albino Bristlenose pleco;
  • Longfin Bristlenose pleco;
  • Super Red Bristlenose pleco;
  • Starlight Bristlenose pleco;
  • Calico Bristlenose pleco.

Bristlenose pleco can grow between 3 and 6 inches long (7.62 to 15 cm). 

Bristlenose pleco behavior

Bristlenose plecos are docile and peaceful fish that are great with other peaceful tank mates. Because plecos are bottom dwellers they are rarely seen on the same line of view as those fish that occupy other parts of the water column.

These fish are nocturnal. This means that bristlnose plecos are quiet during the day. You might even have difficulties in finding them in the tank,                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             due to their camouflaging colors. They like to relax in caves and dark hiding spots.

When the night comes, plecos get much more active. You can see them swimming around the bottom of the tank looking for food. If they find a spot full of algae, they will be eating as much as they can.

Bristlenose plecos are usually calm with other fish species. But when males are together, they might squabble with each other during the breeding season, or for a good hiding spot or cave. However, this does not result in anything serious. The likely outcome is they darting to different parts of the tank. If you have male and female bristlenose plecos, they can chase each other until they are adults and ready to breed.

Bristlenose plecos diet

Bristlenose plecos are omnivores. They like to eat the algae and biofilm built up in the aquarium. However, they cannot survive only by feeding on the algae and biofilm built up. They need a diet composed of proteins and algae wafers. Besides that, bristlenose plecos can eat tiny insect larvae, blanched vegetables like carrots, zucchini, peas, broccoli, and cucumber. Additionally, they also scavenger for food in the substrate. You can occasionally feed them bloodworms.  

Bristlenose plecos breeding 

In a community tank, you should have more females than males since they can get territorial during mating season. Initially, the male looks for a spot so the female can lay her eggs, like a cave or a hiding spot. The male then cleans up the cave and waits for the female.

If she accepts his offer, she will lay her eggs all over the place so the male will fertilize them. The female bristlenose pleco will protect the eggs while the pair waits for them to hatch. This can take from 4 to 10 days. Meanwhile, the male cleans the eggs and aerates them with his tail. 

Bristlenose plecos are protective of their fry. As soon as the eggs hatch, the fry starts to eat their egg sacs until they have grown enough to leave the cave or their hiding spot to swim around the tank. Then you can start feeding them algae if they are not serving themselves first, as well as mashed vegetables. Fry grows very rapidly and they can reach adulthood in 6 months. 

Bristlenose plecos tank setup

Bristlenose plecos need a minimum of a 25-gallon tank so they can swim around freely. Make sure the size will be adjusted if you have them in a community tank. Because they are shy bottom-dwellers, they need a lot of hiding places and caves.

Live plants and driftwood are also welcome. The latter is important as algae grow easily in it, and bristlenose plecos benefit from the biofilm across the wood. It is believed that the bacteria in the biofilm are beneficial to their gut.

Although they are algae eaters and scavengers, that is not enough to keep the tank clean as bristlenose plecos produce a lot of waste. They need a good filtration system to keep the tank clean while aerating the water. A gravel vac is a great option to clean their waste as well as any uneaten food.

Bristlenose plecos thrive in temperatures between 60 and 80 F (15.6 and  26.7  °C) as well as a pH ranging from 6.5 to 7.5. The ideal water hardness should be between 6 to GFC C10 KH. Keeping the water parameter controlled and the tank cleaned is important to avoid any disease to your bristlenose plecos. Otherwise, they might have Ich, bacterial infections, among other diseases.

Additionally, you can pay attention if your bristlenose pleco is regularly swimming up to the surface of the tank. This could mean that either the oxygen levels are low in the bottom of the tank and they need to breathe, or that the ammonia and nitrate levels in the water are high. To avoid this situation, make sure you check your filter, bubbler, and water parameters regularly.

What about betta fish?

Betta fish (Betta splendens), also known as Siamese fighting fish are native to Cambodia, Vietnam, and Thailand. Their natural habitats comprise rice paddies, canals and floodways, and flood fringes in medium to large rivers. Their notorious name stemmed from their aggressive behavior between them and other fish.

Oftentimes, betta fish can even fight their reflection! They can live up to 5 years if taken good care of. Betta fish are used to calm waters so, flow is not a must. On the other hand, a filter is necessary in order to keep the water clean. These fish thrive in temperatures ranging from 75 to 80 F (23.8 to 26.7 °C). The ideal pH should be between 6 to 8.

4 reasons to place your betta and a bristlenose pleco together

Bettas and bristlenose plecos can be great tank mates. Here are the four main reasons that corroborate the former affirmation:

  • Your betta will not see them as a threat;
  • Bristlenose plecos have a very peaceful nature;
  • Bettas and bristlenose plecos have similar water parameters;
  • They will not compete over food.

Your betta will not see them as a threat

One of the most important things to know is whether the new tank mate will pose a threat to your betta. Or the other way around. Bristlenose plecos do not share the same place as bettas in the water column. They are nocturnal, shy, and spend most of the day hidden or scavenging around the gravel. Hence, the likelihood of your betta feeling threatened by them and engaging in a fight is quite low.

Bristlenose plecos have a very peaceful nature

Bristlenose plecos are quite shy and peaceful by nature. They might get a bit aggressive only with other male bristlenose plecos during mating season or when fighting for a hiding spot. But that does not happen that frequently.

Bettas and bristlenose plecos have similar water parameters

Both bristlenose plecos and bettas have water similar parameters. Since bristlenose plecos are hardier than bettas, they can compromise with bettas’ ideal water parameters, such as 78 F (25.6 °C) and pH 7.0.

They will not compete over food

Betta fish are carnivores while bristlenose plecos are omnivores. Hence, they have a slightly different diet. Bristlenose plecos can indeed eat insect larvae and bloodworms, but that is not the main component of their diet. They also eat algae, blanched vegetables, and algae wafers. They also scavenger for uneaten food. Having different diets and the fact that both live in a different level of the water column, make them unlikely to compete over food. 


Bettas and bristlenose plecos can be great tank mates. It is a fact that the temperament of your betta is crucial to make this arrangement work out. Still, the odds are in the bristlenose plecos’ favor.

Because bristlenose plecos are shy and nocturnal bottom-dwellers while bettas are more active during the day, the chances of encounters are reduced.

It is always important to take into account the nature of your betta. If you know he’s aggressive then it’s always best to avoid adding any fish into the tank with him. 

On the other hand, if you know your betta is calm then you’re good to go. Make sure you follow their tank and diet requirements. If you liked this post, comment and feel free to ask us questions about these two singular fishes. Also, make sure you check out the rest of the website! 


Arun, C., M.D. (2021). Beginners guide book on Bristlenose Pleco breeding & nurturing: A comprehensive dummies manual on how to properly provide your sea pet with adequate care such as feeding, good habitat, and necessary treatment to keep it happy. (N/A). 29 p.

Srinivasan, M.  (2013) A complete manual on Ornamental Fish Culture. LAP Lambert Academic Publishing. Saarbrücken, Germany. 222 p.