Are you an aquarium enthusiast looking for more pet fish to add to your aquarium? Are you interested in fish that are not only unique and exciting, but can also help you maintain and keep your tank clean?
Yes, you read that right! You can actually get fish that will help maintain your tank’s ecosystem.
These are known as bottom feeder fish, and they are actually detritivores, meaning they feed on dead or decaying organic matter. So, once you add them to your tank, you simply need to stop worrying about dead matter, algae build-up, and debris completely.
How to Identify Bottom Feeder Fish
So, how do you actually differentiate bottom feeder fish from others? Simply put, these fish are usually found lingering near the substrate in search of food. Some scavenge and consume dead fish, invertebrates, and pests, while others simply feed on algae, dead plants, and other debris.
You will usually find them at the bottom of the aquarium, but there are a few other features that distinctly set them apart from other fish. These include:
Lower mouth
Bottom feeders have lower or inferior mouth placement. This means that their mouth is placed towards the lower side of their bodies, so that it is easier for them to pick up food from the substrate. They can easily feed without having to move their eyes away from prying hunters.
Barbels
They have whiskers called barbels placed near their mouth region. These whiskers are fleshy and serve as sensory organs. They help the fish taste and identify food long before they start to consume it with their mouths.
Suckermouth
Some bottom feeder fish classify as suckermouths. These types of fish include the plecos and other catfish that have suction-shaped mouths. They can literally latch onto surfaces to feed just like a suction cup, which helps prevent them from being thrown away by the current if they are in fast-moving waters.
Flat belly
These fish can also be easily identified through their flat ventral regions. Although not all bottom feeders have the exact kind of flat belly, it is definitely flatter than that of a regular fish. A flat ventral region allows these fish to easily rest and move along the substrate.
The 4 Main Categories
Now that you know how to differentiate between bottom feeders and other aquatic creatures, let’s take a look at some cool bottom feeder types in detail. This will help you decide and eventually pick the best pet for your freshwater aquarium.
But first, let’s look at the four main categories that all freshwater bottom feeder fish fall under:
Catfish
Catfish are a diverse group of fish that fall under this category due to their ray-fins. These fish have defined barbels, and different types grow to various sizes. Some examples include marine catfish, candiru, and coral catfish.
Loaches
Loaches are another category of bottom feeders that usually live in the rivers of Asia, Europe, and America. These freshwater fish love to create their homes in the sand found on the riverbed. They do so by creating and marking broad territories along the river bed. Some examples include the Kuhli loach and Clown loach.
Suckers
Suckers have almost 80 species that are native to North America. They live in flowing rivers and streams. These are not a go-to aquarium pet though, as they do not fare well in warm or unstable water conditions.
Suckers are not suckermouths or dwarf suckers, but are actually a type of catfish. Some examples include the hog sucker and the longnose sucker.
Carps
Carps are native to Asia and Europe and are soft-finned and oily. They have spread to almost all parts of the world today. Some examples include the Prussian carp and koi.
The Best Bottom Feeder Fish for Your Tank
There is a lot of variety to choose from when it comes to bottom feeders, but if you want to keep them as a pet, it is absolutely necessary to pick those that can survive in freshwater and can actually live in an enclosed space. Bottom feeders that meet these criteria include:
Synodontis Catfish
- Scientific name: Synodontis Nigriventris
- Type: Catfish
- Origin: Africa
- Color: Silver to gold with black spots
- Size of full-grown adult: 4 to 10 inches
- Lifespan: 10 years
- Behavior: Nocturnal
- Compatibility: Peaceful but can easily be around African cichlids
- Care: Require plants, decor, caves, and hiding places to feel safe
- Nourishment: Small live food, algae, debris
- Lowest tank size: 30 gallons
- Preferable temperature: 22.2°-25°C
- pH: 7.5 to 8.2
Synodontis Catfish are unique and very beautiful. They are shy and peaceful, but can live with mildly aggressive fishes. They like to be alert and on the move during the nighttime primarily, but can sometimes be seen lingering around during daylight.
Although Synodontis catfish are not very aggressive or bubbly, they do have their own bouts of physical activity every now and then. This is when they are the most fun to watch!
Frozen bloodworm and fish flakes are some examples of food you can add to their diet. These fish are also hardy in nature, and do not catch diseases frequently, but you need to keep nitrate levels low to prevent harm to these catfish.
Bristlenose Pleco
- Scientific name: Ancistrus cirrhosus
- Type: Catfish
- Origin: South America
- Color: Gray, brown, black, albino
- Size of full-grown adult: 3 to 24 inches
- Lifespan: 10 to 15 years
- Behavior: Nocturnal
- Compatibility: Peaceful but can get into fights with other plecos
- Care: Require plants, decor, caves, driftwood, and hiding places to feel safe
- Nourishment: Vegetables, algae, flakes, bloodworms, granules
- Lowest tank size: 30 to 125 gallons
- Preferable temperature: 23.8°-27.7°C
- pH: 6.5 to 7.5
Bristlenose plecos are queer-looking fishing, with a few spikes and suckermouths. These herbivores make excellent pets that help clean substrate and algae build-up in the tank. They can grow to become very large. They also produce tons of waste and constantly eat throughout the night. It is, therefore, a good idea to keep them in large freshwater tanks.
This species is known to survive in a wide range of conditions all over the world, so you can expect them to generally not fall sick or cause trouble in your fish tank. However, even though they are hardy fish, they can still get attacked by fish ich. So, do your research on preventing and treating this infection if you decide to keep a Bristlenose Pleco in your aquarium.
Zebra Loach
- Scientific name: Botia striata
- Type: Loaches
- Origin: Western Ghats of India
- Color: Pale yellow, deep brown-gray with stripes
- Size of full-grown adult: 4 inches
- Lifespan: 10 to 15 years
- Behavior: Nocturnal
- Compatibility: Peaceful and like to live in small shoals
- Care: Require shelters with driftwood, open flower pots, smooth rocks, and large tubes to feel safe
- Nourishment: Catfish food, brine shrimp, bloodworms, daphnia, mosquito larvae, algae, vegetables
- Lowest tank size: 20 gallons
- Preferable temperature: 21°-26°C
- pH: 6.0 to 7.5
As the name suggests, Zebra loaches are colorful fish with stripes on their body similar to a zebra. These fish do not grow to become very large, and love to live in small shoals. They make great pets if you have a small tank as they do not take up too much space and are quite peaceful.
They love to clean up any algae build-up and plant matter present in the substrate or stuck on the aquarium glass. Not only do they help keep the tank clean, but they are also great in versatile conditions. They simply need a well-oxygenated tank and a planted aquarium setting to stay happy.
Zebra loaches are also great at killing pests lingering around in your tank, as they are omnivorous in nature.
Twig Catfish
- Scientific name: Farlowella acus
- Type: Catfish
- Origin: Tropical river basins of Colombia
- Color: Brown with dark stripes
- Size of full-grown adult: 6 to 9 inches
- Lifespan: 10 to 12 years
- Behavior: Nocturnal
- Compatibility: Peaceful and shy
- Care: Require shelters with driftwood, open flower pots, smooth rocks, and large tubes to feel safe
- Nourishment: Algae, blanched vegetables
- Lowest tank size: 20 gallons
- Preferable temperature: 24°-26°C
- pH: 6.0 to 7.0
Twig catfish are shaped exactly like twigs, and they use this to camouflage themselves and prevent attacks from predators. They avoid aggressive fish and are very shy and timid. They also love to stay hidden and often use their suckermouths to latch to their favorite surface to lay motionless in one place.
However, twig catfish are not easy to maintain. They require very clean and well-balanced waters with adequate oxygen levels to thrive.
Bumblebee Goby
- Scientific name: Brachygobius Xanthozonus
- Type: Catfish
- Origin: Thailand and Indonesia
- Color: Black with pale yellow or orange bands
- Size of full-grown adult: 1.5 inches
- Lifespan: 3 years
- Behavior: Nocturnal
- Compatibility: Peaceful and loves to live in small shoals
- Care: Brackish water with sand and numerous hiding spots
- Nourishment: Live or frozen foods such as brine shrimp, daphnia, tubifex worms, bloodworms
- Lowest tank size: 10 gallons
- Preferable temperature: 22°-28°C
- pH: 7.0 to 8.5
The Bumblebee Goby is a cute, tiny fish that resembles small bumblebees. These fish are peaceful and playful, but do love to poke their noses into other people’s business. They also require special water conditions to survive – you will need a rank filled with brackish water with a ton of sand substrate.
Also, these fish do not like to be alone. It is better to keep them in small groups so that no one is isolated and social well-being is maintained. The ideal group size is at least a dozen fish. These fish are small, so it should not be a huge problem to house a dozen in one tank!
Yoyo Loach
- Scientific name: Botia almorhae
- Type: Loaches
- Origin: Pakistan
- Color: Silver with dark markings
- Size of full-grown adult: 2.5 to 6 inches
- Lifespan: 5 to 8 years
- Behavior: Diurnal
- Compatibility: Peaceful but noisy
- Care: Numerous small hiding spots
- Nourishment: Live or frozen foods like snails, mosquito larvae, daphnia, brine shrimps, blackworms, bloodworms
- Lowest tank size: 45 gallons
- Preferable temperature: 22°-27.7°C
- pH: 6.0 to 7.5
Yoyo loaches are peaceful fish that will generally avoid aggressive fish. However, there can be some disagreements within their own kind. They are also noisy, playful, and love to move through the substrate to look for snails and other pests. They can be a great addition to your tank if you have a snail invasion.
Yoyo loaches can also survive in both hard and soft water. A larger tank is more suitable for them though, as they do not like to stay alone. They are very social and will be most happy in groups of at least 5 members. Your Yoyo loaches can even live up to 20 years of age if they are very well cared for.
Siamese Algae Eater
- Scientific name: Crossocheilus oblongus
- Type: Carps
- Origin: Southeast Asia, including Thailand and Malaysia
- Color: Brownish gray with a stripe running on each side
- Size of full-grown adult: 6 inches
- Lifespan: 10 years
- Behavior: Nocturnal
- Compatibility: Peaceful but are quick swimmers and very active
- Care: Do not require fancy tanks
- Nourishment: Algae forms like phytoplankton and periphyton, dead fish, insects
- Lowest tank size: 30 gallons
- Preferable temperature: 24°-26°C
- pH: 6.5 to 8.0
Siamese Algae Eaters are a favorite amongst aquarists. These fish clean up all the algae in your tank. They are also very peaceful yet still active, so they are quite a sight to behold.
They are also low-maintenance and can survive in versatile conditions. The best part is that they are super compatible with all sorts of other fish!
Snails
- Scientific name: Gastropods
- Type: Shell Gastropods
- Origin: Southeast Asia, South America, and Africa
- Color: Tan, olive, maroon, yellow, blue, white
- Size of full-grown adult: 1 to 5 inches
- Lifespan: 2 to 3 years
- Behavior: Nocturnal
- Compatibility: Docile
- Care: Do not require fancy tanks
- Nourishment: Algae forms, dead fish, rotten plants, leftover fish food
- Lowest tank size: 5 gallons
- Preferable temperature: 22°-28°C
- pH: 7.0 to 8.0
There are tons of different kinds of snails that can survive in freshwater. However, you must do your research and carefully pick species that will not breed like crazy and overpopulate your tank.
If you pick the right kind snails can be great pets. Not only are they intriguing and colorful, but they also help clean your tank thoroughly. They are also very docile and generally do not bother any fish or other creatures living in the tank.
Corydoras Catfish
- Scientific name: Corydoras Melanotaenia
- Type: Catfish
- Origin: South America
- Color: Green, bronze, black, albino
- Size of full-grown adult: 1 to 2.5 inches
- Lifespan: 5 years
- Behavior: Nocturnal
- Compatibility: Peaceful
- Care: 2-inch gravel substrate, plants, and hiding places
- Nourishment: Tablets, pellets, fish flakes, plants, vegetables, algae
- Lowest tank size: 20 gallons
- Preferable temperature: 21.1°-23.8°C
- pH: 6.0 to 8.0
Corydoras are simple, low-maintenance, and peaceful fish. These bottom feeders are great for your freshwater aquarium if you really want a couple of active fish fretting about in your tank.
Corydoras love to stay in a group, so it’s best to keep at least 6 or more in one tank. If you don’t then they are less likely to stay happy and will get into fights amongst themselves.
Ornamental Shrimp
- Scientific name: Neocaridina davidi
- Type: Decapod Crustaceans
- Origin: Southeast Asia
- Color: Green-brown, red, yellow, orange, green, blue, violet, black
- Size of full-grown adult: 1 to 2 inches
- Lifespan: 1 to 2 years
- Behavior: Nocturnal and diurnal
- Compatibility: Peaceful but active grazers
- Care: Heavy plantation
- Nourishment: Algae, dead plants, live plants, worms, fish, snails, leftover fish food
- Lowest tank size: 5 gallons
- Preferable temperature: 20°-23.8°C
- pH: 6.0 to 8.0
Shrimps are very similar to snails in terms of hunting algae, clearing off dead organic matter, and keeping the tank tidy. Unlike fish, shrimps are different in structure, so they add a little more diversity to your aquarium. These creatures are fun to watch as they actively look around for food.
They come in a variety of colors, and can be kept in various water conditions depending on the species.
Otocinclus Catfish
- Scientific name: Otocinclus Arnoldi
- Type: Catfish
- Origin: South America
- Color: White or gray with brown stripes
- Size of full-grown adult: 1.5 to 2 inches
- Lifespan: 3 to 5 years
- Behavior: Nocturnal
- Compatibility: Peaceful
- Care: Heavy plantation
- Nourishment: Algae, fresh vegetables
- Lowest tank size: 5 gallons
- Preferable temperature: 21°-25.5°C
- pH: 6.5 to 7.5
Otocinclus catfish prefer to live in schools and should not be isolated. These fish can peacefully live with their own kind or other smaller fishes. Otocinclus are peaceful fish that love heavy plantations and are avid algae eaters.
However, they do produce a good amount of waste, and since you should keep at least 10 of them together, you can expect a lot of waste! The only thing you really need to do is keep the tank clean. Otherwise, these are very cute fish!
Kuhli Loach
- Scientific name: Pangio Kuhlii
- Type: Loaches
- Origin: Southeast Asia
- Color: Brown with bright yellow and orange bands
- Size of full-grown adult: 3 to 5 inches
- Life span: 10 years
- Behavior: Nocturnal
- Compatibility: Peaceful
- Care: Sand and fine gravel mix, heavy plantation, hiding spots
- Nourishment: Pellets, flakes, live and frozen foods like bloodworms, mosquito larvae, and brine shrimps
- Lowest tank size: 20 gallons
- Preferable temperature: 24°-29.5°C
- pH: 5.5 to 6.5
Kuhli Loaches are small, peaceful fish that love to stay in groups of 6 or more. They look like eels and usually come out at night in search of food. Their unique build can help you add a bit more variety to your freshwater tank.
They love to hide, hate being bothered, and don’t pick fights with other fish.
The Worst Bottom Feeder Fish for Your Tank
Let’s now look at some less popular choices for bottom feeder fish. While they are not the ideal addition to your tank, they may be a great option for you if you are willing to put in more effort:
Crayfish
- Scientific name: Cambarus sp.
- Type: Crustaceans
- Origin: Louisiana, USA
- Color: Brownish-yellow, red, green, dark brown
- Size of full-grown adult: 3 to 4 inches
- Lifespan: 1 to 20 years
- Behavior: Nocturnal
- Compatibility: Aggressive
- Care: Plants, woody debris, rock, sand, gravel
- Nourishment: Snails, insects larvae, worms, tadpoles, plants
- Lowest tank size: 5 to 10 gallons
- Preferable temperature: 18°-25°C
- pH: 6.5 to 7.0
Crayfish are unique creatures that are very similar to lobsters. However, as they grow larger and stronger, they can pose a great threat to other aquatic life. Therefore, it is not preferable to keep them with small fish and snails that might become their prey.
You might also have to pick ones that seem slightly more docile. Crayfish can just up and walk out of your aquarium, especially those that are not used to captivity. All in all, they are only great if you want to house a single crayfish, as they do like to fight within their own species a lot as well!
Tiger Shovelnose Catfish
- Scientific name: Pseudoplatystoma fasciatum
- Type: Catfish
- Origin: Suriname, Corantijn and Essequibo
- Color: Dark silver with black stripes
- Size of full-grown adult: 3 feet
- Lifespan: 18 to 25 years
- Behavior: Nocturnal
- Compatibility: Aggressive
- Care: Numerous small hiding spots
- Nourishment: Live fish, meat scraps, earthworms, tablets
- Lowest tank size: 400 gallons (for a full-grown adult)
- Preferable temperature: 22°-26°C
- pH: 6.0 to 7.5
The Tiger Shovelnose Catfish is quite gigantic in terms of length, especially once it reaches its adult size. These fish are nocturnal predators, and tend to hunt down other smaller fish.
You need a very large tank to keep them, and it is best to keep them away from fish and pets you do not want to be eaten!
Chinese Algae Eaters
- Scientific name: Gyrinocheilus Aymonieri
- Type: Carps
- Origin: Laos, Vietnam, Thailand
- Color: Pale brown
- Size of full-grown adult: 5 to 10 inches
- Lifespan: 5 to 10 years
- Behavior: Nocturnal
- Compatibility: Aggressive
- Care: Rocks and caves
- Nourishment: Algae, plants, algae wafers
- Lowest tank size: 55 gallons (for a full-grown adult)
- Preferable temperature: 24-27°C
- pH: 6.5 to 7.5
These eel-like fish grow to be very long and usually require huge freshwater tanks to thrive. Plus, they start to get very aggressive as they mature. The worst part is Chinese Algae Eaters can latch onto other fish and damage their scales and skin.
Frequently Asked Questions
Which bottom feeder fish is best?
Definitely, the one you love the most! Any bottom Feeder should be great as long as you like keeping it, they’re compatible with other fish in your aquarium, and can help clean up your tank.
You may even find that you love aggressive bottom feeders more. If that is the case, make sure you ensure the safety of your other fish, or you can simply put up an entirely new tank for your new pets!
Do bottom feeder fish eat poop?
No kind of fish actually eats poop. They do happen to fill up your aquarium with poop, though. Even the crustaceans will just dodge it. Your best bet is to manually remove all poop by using a gravel vacuum.
Do bottom feeders keep the tank clean?
Yes! Bottom feeders are found usually lingering near the substrate in search of algae, dead fish, decaying organic matter, and even pests. Bottom feeders are a great way to help balance your aquarium’s ecosystem and reduce the build-up of dead organic matter and algae.
Are Goldfish top or bottom feeders?
Goldfish are a type of carp that naturally prefer to feed on the bottom. These bottom feeders love to eat both frozen and live foods such as worms, larvae, brine shrimps, and even some vegetables.
How do you care for a bottom feeder?
Most bottom feeders love sand and gravel substrates. They also love hiding between plants, in caves, and in other spots they find. Driftwood and light obstruction effects are some of their favorite things. This is why it is essential to make sure your aquarium is properly set up, keeping these things in mind. It is also essential to do your research and feed your bottom feeders adequately.
Conclusion
Now that we have looked at some popular bottom feeders in detail, it is time to pick ones that are most suited to your aquarium. Make sure you look into every little detail such as compatibility, behavior, and even diet.
Most aquarists do their own research before picking new pets, and you should do so as well. You must assess how much money you are willing to spend on the purchase of the fish, their maintenance, food, equipment, and possibly even a new tank if necessary.
It is also a great idea to pick ones that are easier to take care of if you are a newbie. Fish that are harder to care for should only be kept as pets if you are an expert aquarist, since negligence or accidents could easily kill them.
Also, remember to always keep fish that will not kill each other off in one tank. Aggressive species should be kept separately. If you keep all of this in mind, you can easily move on to picking a new pet. So, go on and pick fish with patterns and colors that you really love!

Hi, my name is Adam and I’m an aquarium enthusiast! I didn’t discover the joys of being an ‘aquarium fanatic’ (as some of my friends call me!) until I was in my 20’s. When I first started out I found it difficult to find all the information I needed so I started this website to compile all the useful information I can think of. Enjoy!
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