How to Care for Bristlenose Plecos
Bristlenose Plecos are one of the most popular freshwater fish in the aquarium hobby, and for good reason. They’re hardy, peaceful, full of personality, and come in a wide range of colours and fin types including Common, Albino, Super Red, Calico, Longfin varieties and a whole bunch of L numbers of all shapes and sizes.
However, Bristlenose are also one of the most misunderstood fish sold in aquariums. Many losses happen not because they’re delicate, but because their basic needs are overlooked.
This guide covers how to properly care for all types of Bristlenose Plecos, focusing on what they need to survive, stay healthy, and thrive in the best conditions possible.
1. Tank Requirements: Setting Them Up for Success
A Bristlenose Pleco may be small when purchased, but they are not a nano fish they can grow up to 15cm!
Minimum tank size: 75 litres
Ideal tank size: 100 litres or more
Tank level: Bottom dweller
Floor space matters more than height, they can live perfectly fine in long shallow tanks as they prefer length over height. Bristlenose spend most of their time grazing along surfaces, hiding in caves, or resting under driftwood.
While Bristlenose are hardy, they do poorly in unstable or cramped environments. A larger tank provides better water stability and more grazing surfaces, which directly improves their health.
2. Water Parameters & Stability
Bristlenose Plecos are adaptable, but stability is far more important than chasing exact numbers.
Temperature: 26–28°C
pH range: 6.5–7.5
Water type: Tropical freshwater
💬 This is just a baseline for the more common specie and may vary between different species of bristlenose and L number plecos.
Sudden changes in temperature or water chemistry are one of the biggest causes of stress and unexplained deaths. Regular, consistent weekly water changes are far safer than infrequent large ones.
- Tip: When performing routine maintenance, aim to match new water temperature closely to the tank to avoid unnecessary stress.
- Breeding Tip: Slightly cooler water changes can sometimes trigger breeding behaviour in Bristlenose Plecos. This mimics seasonal rainfall in their natural environment. Many breeders report increased success when cooler water changes are done during periods of real rainfall. Avoid extreme temperature drops cooler, but not cold, is the key.
Aim for:
✅️ Weekly water changes
✅️ Gentle gravel cleaning around (not inside) hiding areas
✅️ Dechlorinated water matched closely to tank temperature unless intentionally attempting to trigger breeding
3. Filtration & Oxygenation
Clean, oxygen-rich water is essential for Bristlenose Plecos.
They prefer:
✅️ Moderate water flow
✅️ Mature biological filtration
✅️ Well-oxygenated water
Sponge filters, hang-on-back filters, and canister filters all work well when appropriately sized. Many keepers successfully run a sponge filter alongside a main filter to increase biological filtration and provide a backup.
Avoid over-cleaning filters, as beneficial bacteria are critical for keeping ammonia and nitrite at zero.
If you would like to know more about ammonia, nitrite and how its linked to the cycle of your aquariums water conditions, feel free to check out our page on the nitrogen cycle!
4. Diet: What Bristlenose Plecos Actually Eat
One of the most common mistakes is assuming Bristlenose can survive on algae alone.
While they do graze on algae and biofilm, this is not a complete diet.
A proper Bristlenose diet includes:
✅️ High-quality algae wafers
✅️ Sinking pellets (algae-based and protein-inclusive)
✅️ Blanched vegetables such as zucchini, cucumber, spinach, and pumpkin
Vegetables should be removed after 12–24 hours to prevent decay of the vegetable which can lead to ammonia spikes.
- Tip: Feed Bristlenose just before or after lights-out or during low-light periods. They are naturally nocturnal and are far more confident feeders when the tank is calm and dim.
Driftwood Is Essential!
Driftwood is not optional for Bristlenose Plecos.
They rasp on wood to aid digestion and graze on the micro-organisms that grow on its surface. Tanks without driftwood often lead to digestive issues and long-term health problems.
- Tip: If a Bristlenose appears skinny despite regular feeding, lack of driftwood is often the cause.
The Algae Myth: Cleaners In, Waste Out
Bristlenose Plecos do eat a noticeable amount of algae and biofilm, which can help keep surfaces cleaner. However, what many people don’t realise is that everything they eat has to come back out.
Bristlenose are constant grazers, which means they also produce a large amount of waste, also much of the wood that they rasp on also passes through them as little micro chips as they cannot be digested by them. In smaller aquariums, this can quickly lead to cloudy water, increased nitrate levels, and the need for more frequent maintenance.
- Tip: Adding a Bristlenose to a small tank without adequate filtration often creates more work, not less. They are not a substitute for regular cleaning or water changes.
This is why appropriate tank size, strong biological filtration, and consistent maintenance are essential when keeping Bristlenose Plecos.
5. Driftwood, Caves & Hiding Places
Bristlenose Plecos are nocturnal and naturally shy.
Every Bristlenose tank should include:
✅️ Driftwood
✅️ At least one cave per Pleco
✅️ Shaded hiding areas
Males are territorial, especially as they mature. Insufficient caves often result in stress or fighting, even in otherwise peaceful tanks.
Ceramic caves, rock caves, and hollow wood all work well, as long as the Pleco can fully fit inside.
- Tip: If keeping more than one Bristlenose, provide more caves than fish. Extra caves significantly reduce territorial disputes.
6. Plants & Aquascaping Compatibility
Bristlenose Plecos are generally plant-safe.
They do not eat healthy plants, but may rasp at:
- Soft or damaged leaves
- Decaying plant matter
Hardy plants such as Anubias, Java Fern, Cryptocoryne, Vallisneria, and Amazon Swords work particularly well.
Live plants also improve water quality and create shaded areas, which Bristlenose appreciate.
7. Lighting Preferences
Bristlenose Plecos prefer low to moderate lighting.
Excessively bright lighting can cause them to hide constantly, reducing feeding opportunities and increasing stress. In planted tanks, balance lighting intensity with floating plants, hardscape, or shaded areas.
- Tip: If your Bristlenose only appears at night, strong lighting may be discouraging natural daytime activity.
8. Behaviour & Tank Mates
Bristlenose Plecos are peaceful and well-suited to many community aquariums.
They coexist well with:
✅️ Tetras
✅️ Guppies
✅️ Corydoras
✅️ Rasboras
✅️ Peaceful cichlids
✅️ Many other catfish species
Avoid housing multiple males in small tanks unless there are plenty of caves. Most aggression involves territory disputes rather than actual harm, but chronic stress should be avoided.
9. Breeding Behaviour (Understanding the Basics)
Bristlenose Plecos are cave spawners with fascinating and very natural breeding behaviour.
A mature male will claim a cave or hollow and clean it thoroughly. When a female is ready, she enters the cave to lay eggs, after which the male fertilises and guards them.
The male fans the eggs constantly to keep them oxygenated and fungus-free, removes infertile eggs, and defends the site from other fish. Eggs typically hatch within 3–5 days, with fry remaining in the cave until their yolk sacs are absorbed.
- Tip: Even if you’re not trying to breed Bristlenose, providing caves is essential. This behaviour explains why males become territorial and why missing caves often leads to stress.
10. Common Mistakes That Kill Bristlenose Plecos
Most Bristlenose losses are preventable. The most common issues include:
❌️ No driftwood in the tank
❌️ Assuming algae is enough food
❌️ Keeping them in tanks that are too small
❌️ Poor or unstable water quality
❌️ Over-cleaning filters
❌️ Treating them as “clean-up fish” rather than living animals
Addressing these basics dramatically improves survival and long-term health.
Final Thoughts: Simple Care Done Right
Bristlenose Plecos are hardy, rewarding fish when kept correctly. They don’t require complicated setups, like all fish they just need the right fundamentals: clean water, stable conditions, proper food, driftwood, and places to hide.
If you’re looking to add one to your aquarium, explore our Bristlenose Pleco Collection, featuring hardy, well-established fish raised with proper diets and suitable environments from an early age, bred for quality, strong genetics and vitality to thrive.
Keeping it simple is often the key to keeping fish alive and healthy, Bristlenose Plecos are no exception! But keep to the basics above and these fish will thrive in your aqaurium for years to come.