Every aquarist dreams of an aquarium that stays crystal clear with minimal maintenance. It’s no surprise, then, that so-called “cleaner fish” are some of the most popular species in the hobby. From algae-eating Plecos to hardworking Corydoras, these fish are often marketed as natural cleaners that will keep your aquarium spotless.
While many species do play a valuable role in consuming algae, leftover food or detritus, it’s important to understand that no fish can completely clean an aquarium for you. Regular maintenance, water changes and good filtration remain essential for a healthy aquarium.
In this guide, we’ll introduce 15 of the best freshwater fish that help keep your aquarium tidy, explain what they actually clean and highlight the limitations of each species.
Can Fish Really Clean an Aquarium?
The simple answer is yes—but only to a point.
Many fish naturally graze on:
- Soft algae
- Biofilm
- Leftover food
- Detritus
- Decaying plant material
However, they do not:
- Replace water changes
- Vacuum gravel
- Clean filter media
- Remove fish waste completely
- Solve poor water quality
Think of these fish as helpful members of your aquarium’s maintenance team rather than replacements for routine care.
What Makes a Good “Cleaner Fish”?
The best clean-up species are generally:
- Peaceful
- Hardy
- Active foragers
- Suitable for community aquariums
- Helpful in controlling algae or leftover food
Different species specialise in different tasks, so understanding their natural behaviour is important.
1. Bristlenose Pleco (Ancistrus Species)
The Bristlenose Pleco is one of the best-known algae eaters in the hobby and an excellent alternative to the much larger Common Pleco.
They spend much of the day attached to glass, rocks and driftwood, grazing soft algae and biofilm.
What They Clean
- Soft green algae
- Brown algae (diatoms)
- Biofilm
- Some leftover food
Adult Size
12–15 cm
Minimum Aquarium Size
90 litres
Best For
Community aquariums and planted tanks.
2. Otocinclus Catfish (Otocinclus species)
Tiny, peaceful and hardworking, Otocinclus are among the best algae eaters available for smaller aquariums.
They constantly graze algae from plants without damaging delicate leaves.
What They Clean
- Soft algae
- Diatoms
- Biofilm
Adult Size
4–5 cm
Minimum Aquarium Size
60 litres
Best For
Planted aquariums.
Otocinclus should only be introduced to mature aquariums with established algae growth.
3. Siamese Algae Eater (Crossocheilus siamensis)
Widely regarded as one of the most effective algae-eating fish, the Siamese Algae Eater is particularly well known for consuming nuisance hair algae.
Unlike many algae eaters, they continue grazing throughout adulthood.
What They Clean
- Hair algae
- Black Beard Algae (young growth)
- Thread algae
- Biofilm
Adult Size
14–16 cm
Minimum Aquarium Size
125 litres
4. Panda Garra (Garra flavatra)
Panda Garra are energetic fish that constantly graze surfaces using their specialised sucker mouths.
They’re increasingly popular thanks to their attractive markings and algae-eating habits.
What They Clean
- Biofilm
- Soft algae
- Organic growth
Adult Size
8–10 cm
Minimum Aquarium Size
90 litres
5. Corydoras Catfish (Corydoras Species)
Corydoras are often mistakenly described as “clean-up fish.”
While they don’t actively clean algae, they search the substrate for uneaten food.
What They Clean
- Leftover fish food
- Organic debris
Adult Size
5–7 cm
Minimum Aquarium Size
75 litres
Important
They should never be expected to survive solely on scraps.
Feed them sinking foods daily.
6. Rubber Lip Pleco (Chaetostoma Species)
Rubber Lip Plecos remain smaller than many Pleco species and spend most of their time grazing algae from hard surfaces.
What They Clean
- Soft algae
- Biofilm
- Diatoms
Adult Size
10–13 cm
Minimum Aquarium Size
90 litres
7. American Flag Fish (Jordanella floridae)
This colourful North American native has earned a reputation as an excellent algae grazer.
They’re one of the few freshwater fish known to consume certain filamentous algae.
What They Clean
- Hair algae
- Thread algae
- Soft algae
Adult Size
6 cm
Minimum Aquarium Size
75 litres
Some individuals can become territorial during breeding.
8. Chinese Algae Eater (Gyrinocheilus aymonieri)
Chinese Algae Eaters are often sold as algae eaters when young.
Juveniles graze algae effectively, but adults frequently become territorial and lose interest in algae.
What They Clean
- Soft algae (juveniles)
- Biofilm
Adult Size
20–28 cm
Minimum Aquarium Size
180 litres
They’re generally not recommended for peaceful community aquariums due to their adult behaviour.
9. Florida Gar (Lepisosteus platyrhincus)
Despite occasionally appearing in “cleaner fish” lists online, Florida Gar are not aquarium cleaners.
They’re predatory fish that require enormous aquariums or ponds.
What They Actually Do
Nothing related to aquarium cleaning.
They are included here simply because they’re often mistakenly believed to help keep tanks clean.
Adult Size
Over 1 metre
Recommendation
Not suitable for the vast majority of home aquariums.
10. Twig Catfish (Farlowella Species)
Twig Catfish are masters of camouflage, resembling small sticks or branches.
They’re gentle algae grazers best suited to peaceful planted aquariums.
What They Clean
- Biofilm
- Soft algae
- Diatoms
Adult Size
15–18 cm
Minimum Aquarium Size
90 litres
11. Molly (Poecilia sphenops)
Mollies aren’t specialist algae eaters, but they happily graze soft algae throughout the day.
What They Clean
- Soft algae
- Biofilm
- Plant surfaces
Adult Size
8–10 cm
Minimum Aquarium Size
90 litres
12. Hillstream Loach (Sewellia lineolata)
Hillstream Loaches naturally inhabit fast-flowing rivers where they graze algae from rocks.
Their unique flattened bodies allow them to cling to surfaces.
What They Clean
- Biofilm
- Soft algae
- Diatoms
Adult Size
6–8 cm
Minimum Aquarium Size
75 litres
Strong water movement is essential.
13. Clown Pleco (Panaqolus maccus)
Clown Plecos spend much of their time rasping driftwood and grazing biofilm.
Unlike algae specialists, they also require wood as part of their diet.
What They Clean
- Biofilm
- Some algae
- Driftwood surfaces
Adult Size
8–10 cm
Minimum Aquarium Size
90 litres
14. Flying Fox (Epalzeorhynchos kalopterus)
Flying Foxes consume algae when young, although they become more omnivorous as they mature.
What They Clean
- Soft algae
- Biofilm
Adult Size
14 cm
Minimum Aquarium Size
125 litres
Adults can become territorial.
15. Brochis Catfish (Brochis splendens)
Closely related to Corydoras, Brochis Catfish spend their day searching the substrate for leftover food.
What They Clean
- Uneaten food
- Organic debris
Adult Size
8–9 cm
Minimum Aquarium Size
125 litres
What About Shrimp and Snails?
Although this guide focuses on fish, some of the best aquarium cleaners aren’t fish at all.
Excellent additions include:
- Amano Shrimp
- Cherry Shrimp
- Nerite Snails
- Mystery Snails
These invertebrates often outperform many fish when it comes to algae control.
What Cleaner Fish Can’t Do
No matter how efficient your clean-up crew is, they cannot:
- Remove nitrate
- Perform water changes
- Clean filters
- Eliminate algae outbreaks caused by poor water quality
- Replace gravel vacuuming
A healthy aquarium always requires regular maintenance.
Building the Perfect Clean-Up Crew
Rather than relying on a single species, many aquarists combine several.
For example:
Community Aquarium
- Bristlenose Pleco
- Six Corydoras
- Six Otocinclus
Planted Aquarium
- Otocinclus
- Amano Shrimp
- Nerite Snails
Larger Aquarium
- Siamese Algae Eaters
- Bristlenose Pleco
- Corydoras
Each species performs a slightly different role.
Common Mistakes
Buying a Common Pleco
Common Plecos can exceed 45 cm in length.
For most home aquariums, Bristlenose Plecos are a far better choice.
Expecting Cleaner Fish to Eliminate Maintenance
No fish can replace water changes or proper filtration.
Underfeeding Bottom Feeders
Cleaner fish still require appropriate foods.
Many benefit from:
- Algae wafers
- Sinking pellets
- Fresh vegetables
Overstocking
Adding too many clean-up fish increases waste production.
Choose species carefully based on your aquarium size.
Frequently Asked Questions
Which fish is best for eating algae?
The Siamese Algae Eater, Bristlenose Pleco and Otocinclus are among the most effective freshwater algae eaters.
Which fish cleans the substrate?
Corydoras and Brochis Catfish constantly search the substrate for leftover food, although they don’t clean fish waste.
Do Plecos clean fish poo?
No. Plecos eat algae, biofilm and some plant material, but they do not consume fish waste.
Can cleaner fish live together?
Many species are compatible, provided your aquarium is large enough and offers adequate hiding places.
Do I still need to clean my aquarium?
Absolutely. Cleaner fish support your maintenance routine but never replace it.
Final Thoughts
Cleaner fish can make a valuable contribution to a healthy aquarium, helping to control algae, consume leftover food and keep surfaces free from biofilm. However, it’s important to understand their limitations. No fish can replace regular maintenance, water changes or good aquarium husbandry.
By selecting species suited to your aquarium and understanding what they actually eat, you can build an effective clean-up crew that complements your maintenance routine while adding interest and diversity to your aquarium.
At Charterhouse Aquatics, we stock a wide range of algae-eating fish, freshwater shrimp, aquarium snails, filters, algae control products, fish foods and maintenance equipment to help keep your aquarium looking its best. Whether you’re creating a planted nano aquarium or a large community tank, our expert team can help you choose the ideal clean-up crew for your setup.
