12 Types of Sucker Fish Ranked by Size

Written by Lev Baker
Updated: June 15, 2023
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Sucker fish are a diverse and captivating group of aquatic creatures. One of the most intriguing aspects of sucker fish is their range in size, from tiny species to massive ones that can grow several feet. This diversity in size is a testament to the adaptability and evolution of sucker fish, as they have developed specialized characteristics and behaviors to thrive in different aquatic environments.

In this article, we’ll take a closer look at the different types of sucker fish ranked by size, providing an intriguing glimpse into the underwater realm of these amazing creatures. Here’s a preview of the featured fish:


Now read on for more information about these unique fish, moving from smallest to largest!

12. Dwarf Suckermouth (Otocinclus vittatus) — Up to 2 Inches

Closeup of an otocinclus in planted aquarium

The dwarf suckermouth is a small fish, generally reaching only up to two inches.

©Swapan Photography/Shutterstock.com

Indigenous to the South American region, the dwarf suckermouth is a small sucker fish that live primarily in the Amazon River basin and a few other river systems.

These fish are easily identifiable by their brown dorsal color, black stripe that runs along the body’s length, and underslung mouth that functions as a sucker. Gender identification of this species is challenging as females are marginally larger than males and only distinguishable from above or below. They grow up to only 2 inches in length.

The dwarf suckermouth is a proficient consumer of most types of algae present on leaves, hard surfaces, and glass. 

They primarily cling to substrates using their suckermouth. They usually frequent small streams or on the margins of larger rivers. Due to their active swimming behavior, catching them with a net can be a challenging task.

11. Zebra Pleco (Hypancistrus zebra) — Up to 4 Inches

zebra pleco swimming

The zebra pleco diet is quite diverse, and it includes brine shrimp and bloodworms.

©Pavaphon Supanantananont/Shutterstock.com

The zebra pleco, a type of catfish, is a small fish that can grow up to 4 inches long. They have a sucker-like mouth with four whiskers and a striking black and white striped body. Unlike other fish species, the zebra pleco has armored scutes covering its body instead of scales, which are similar to the scutes found on the skin of crocodiles and bird feet.

Zebra plecos have a diverse diet, which includes brine shrimp, bloodworms, and occasionally algae wafers and blanched vegetables.

These fish are native to the Rio Xingú basin in Brazil, a freshwater tributary of the Amazon River with fast-moving and oxygen-rich waters. As nocturnal creatures, they prefer to reside in deeper waters amidst rocks and fallen trees.

Male zebra plecos, in particular, can be very territorial and aggressive toward other males.

10. Bristlenose Pleco (Ancistrus cirrhosus) — Up to 6 Inches

White Fish - Bristlenose Pleco

Only growing up to about six inches, bristlenose catfish are relatively small.


Bristlenose catfish, or bristlenose plecos, are a distinct and somewhat polarizing species in the aquarium community. While some enthusiasts may find their looks strange or unsettling, others appreciate their unique and intriguing appearance.

These catfish are relatively small, growing up to 6 inches in length. They display colors ranging from brown and green to gray, adorned with white or yellow spots. Some specimens also exhibit uneven coloring, with darker or lighter patches on different parts of their bodies.

In their natural habitat, bristlenose plecos survive mainly on algae. However, they can eat biofilm, vegetables other tank residues in tanks. They originate from the fast-moving waters of the Amazon River Basin in South America.

Known for their docile temperament, bristlenose plecos make great tankmates with other peaceful species.

9. Snowball Pleco (Hypancistrus inspector) — Up to 6.3 Inches

dwarf snowball pleco swimming

One of the smallest pleco fish, the dwarf snowball, has white polka dots all over its body.


The snowball pleco is a stunning and peaceful addition to any aquarium due to its hardiness and non-destructive nature toward plants. This fish also helps keep the tank clean by scavenging and consuming uneaten fish food.

This fish is a member of the Loricariidae family, a group of South American suckermouth catfishes. Large, eye-catching, white polka dots cover its black body. Adults growing up to 6.3 inches long. The snowball pleco is an omnivorous species that feeds on a range of foods in the wild, including animals, algae, detritus, and seeds.

In the wild, the snowball pleco primarily lives in the Rio Negro, a blackwater river that has a much higher level of acidity than other bodies of water.

8. Rubber Lip Pleco (Chaetostoma milesi) — Up to 7 Inches

Rubber Lip Pleco or Chaetostoma milesi

With its high-resting eyes, the rubber lip pleco can spot predators while scavenging at the bottom of

bodies of water


© Ictiologia Universidad Católica de Oriente/Wikimedia Commons – License

The rubber lip pleco is a freshwater catfish originating from South America. These fish have a distinctive large sucking hole for a mouth, with a snout that bends upwards towards the top of their head. Their body tapers towards the base of their fin near their eyes, which are located above the rest of their body to help them spot predators while scavenging on the bottom. They can grow up to 7 inches in length.

Unlike other pleco species, the rubber lip pleco is primarily an algae eater in the wild. They typically live in the Apure River in Venezuela and the Magdalena River in Colombia.

The rubber lip pleco is known for its peaceful temperament and mellow activity level. They are often observed parked in one place or slowly moving around a hiding spot for protection.

7. Chinese Algae Eater (Gyrinocheilus aymonieri) — Up to 11 Inches

Macro close up of a Chinese Algae Eater (Gyrinocheilus aymonieri) in fish tank with blurred background

Chinese algae eaters attach to rocks via their mouths to feed primarily on algae, as their name suggests.

©Joan Carles Juarez/Shutterstock.com

The Gyrinocheilus aymonieri, commonly known as the Chinese algae eater, is a freshwater fish found in various parts of Southeast Asia. It is sought after as a local food source and for the aquarium trade.

These fish have long, slender bodies and tiny fins. One of their distinguishing characteristics is their small dorsal fin with several firm rays, lending them a spiky appearance. Adults can grow up to 11 inches in length.

In their natural habitat, Chinese algae eaters attach themselves to rocks using their “sucker” mouths and feed primarily on algae. They can be found in large and medium-sized lakes, rivers, and flooded fields.

Chinese algae eaters have a semi-aggressive nature and tend to be more reclusive, preferring to hide rather than exhibit flashy or active behaviors.

6. Northern Hog Sucker (Hypentelium nigricans) — Up to 17 Inches

Northern Hog Sucker Hypentelium nigricans

Able to reach up to 17 inches, northern hog suckers are medium-sized fish.

©Brian Gratwicke/Wikimedia Commons – License

The northern hog sucker is a freshwater, ray-finned sucker fish characterized by its medium-sized, elongated body and a sizable, rectangular, rigid skull. This unique head structure has a concave area between its eyes. Its mouth is situated at the snout’s end on the ventral side, with extendable lips covered in small bumps. These fish can reach up to 17 inches in length.

Their primary food sources include insect larvae, crustaceans, mollusks, diatoms, and minimal plant matter. The northern hog sucker is a predominant and widely dispersed stream-dwelling fish species in the Ozarks region. It favors stable streams with transparent water, moderate to rapid currents, and a gravel or rocky base.

These fishes are less appealing for consumption compared to other sucker species due to the large, bony head, which results in a reduced amount of edible flesh.

5. White Sucker (Catostomus commersonii) — Up to 23 Inches

White Sucker Fish

White suckers are not completely white. They have a black-to-brass color along their backs, with cream-colored underbellies.

©RLS Photo/Shutterstock.com

Native to North America, the white sucker lives in various parts of the United States. They have a cylindrical shape, with a blunt snout and a fleshy mouth that points downwards. They use their downward mouth for bottom feeding. The fish has relatively large, visible scales, although they are not as big as those seen in fallfish.

Adult white suckers have a coloration that ranges from black to brass on their backs, while their underbellies are cream-colored. The maximum length they can reach is around 23 inches.

White suckers typically frequent both lakes and rivers, and they prefer shallow waters. They primarily feed on worms, clams, insect larvae, and fish eggs. However, they do eat other small fish occasionally.

These fish are quite resilient and can adapt to harsh water conditions that other fish would not survive. 

4. Largescale Sucker (Catostomus macrocheilus) — Up to 24 Inches

A largescale sucker and black background

In the western waterways of Montana live largescale suckers.

©Usha Roy/Shutterstock.com

The largescale sucker is a native fish species of the western waterways of Montana. Distinguished by its rounded snout and downturned mouth on the ventral side, it differs from other fish with mouth placement at the head’s end. Additionally, this fish boasts expansive scales and a slim tail base. Adult largescale suckers can grow up to 24 inches in length.

Their primary diet consists of periphyton and insect larvae. As a vital prey source for numerous vertebrate predators, such as other fish and birds, the largescale sucker plays a pivotal role in sustaining the food chain within its ecosystem. This fish commonly lives in the more tranquil sections of rivers and streams, as well as in lakes.

Unfortunately, a considerable number of anglers in the Pacific Northwest hold misconceptions about this fish species and often eliminate them based on the erroneous belief that they negatively affect salmon and trout populations.

3. Longnose Sucker (Catostomus catostomus) — Up to 25 Inches

Longnose Sucker or Catostomus catostomus

Longnose suckers live in areas of North America, Siberia, and Russia.

©NOAA Great Lakes Environmental Research Laboratory/Public Domain – License

The longnose sucker is a freshwater fish that lives in various areas in North America, and certain rivers in eastern Siberia, Russia. It has a cylindrical body, a unique horizontal mouth, and a long, rounded snout. The fish’s colors range from olive to gray on its upper part and white or cream on the lower side. 

During the breeding season, males become darker, and females can have a green to gold hue on their upper body, with both sexes sporting red lateral stripes. The species can grow up to 25 inches in length.

Longnose suckers typically feed on invertebrates found on the bottom of streams or lakes, slowly swimming along the riverbed in search of prey. These fish thrive in warm, shallow, and murky rivers and lakes.

Although the longnose sucker’s flesh is white and flaky, it is quite bony. The fish has been utilized for various purposes throughout the years, including as bait and dog food, and its fillets have even been consumed by humans, often referred to as mullet.

2. Blue Sucker (Cycleptus elongatus) — Up to 40 Inches

The Yellowstone River in Yellowstone Park has been rated as one of the Outstanding National Resource Waters by the National Park Service, which means it is clean enough for the sensitive blue sucker.

©iStock.com/T Schofield

The blue sucker, a member of the suckerfish family, boasts impressive longevity, with certain individuals living for more than four decades.

Commonly inhabiting large watercourses, such as the Missouri and Yellowstone Rivers, this fish’s slender body, elongated dorsal fin, and unique blue coloring distinguish it. Primarily feeding along the riverbed, the blue sucker consumes a range of aquatic insects, insect larvae, crustaceans, plant matter, and algae.

The blue sucker’s presence is indicative of well-oxygenated, unpolluted waters, as it is highly sensitive to water contamination. As a result, these fish are frequently observed in rivers. Over the years, blue sucker populations have experienced a significant decline, which is attributed to habitat fragmentation.

1. Bigmouth Buffalo (Ictiobus cyprinellus) — Up to 49.5 Inches

Bigmouth Buffalo Fish
Reaching nearly 50 inches, the bigmouth buffalo is a massive fish.

Native to North America, the bigmouth buffalo is one of the biggest species of sucker fish you can find in freshwater. This fish is characterized by its sizeable head, broad rounded body, and expansive lips that form a sucker-like mouth. Unlike other buffalo fish, its mouth faces forward rather than downward.

Exhibiting a wide range of colors, bigmouth buffalos generally have an olive-brown hue accompanied by dark fins.

Primarily dwelling in the channels, deep pools, and backwaters of variously-sized rivers, as well as lakes and sizable reservoirs, the bigmouth buffalo is often observed swimming in schools near the bottom or in mid-water. As a benthic feeder, its diet includes aquatic plants, copepods, cladocerans, small fish, fish eggs, and aquatic insects.

Bigmouth buffalos are adversely impacted by dams, which hinder their mobility and access to appropriate spawning grounds. In addition to being susceptible to winterkill, these fish are also at high risk of overexploitation due to fishing practices.

Summary of 12 Types of Sucker Fish Ranked by Size:

Rank in SizeCommon NameScientific NameSize in Inches
1.Bigmouth BuffaloIctiobus cyprinellusUp to 49.5
2.Blue SuckerCycleptus elongatusUp to 40
3.Longnose SuckerCatostomus catostomusUp to 25
4.Largescale SuckerCatostomus macrocheilusUp to 24
5.White SuckerCatostomus commersoniiUp to 23
6.Northern Hog SuckerHypentelium nigricansUp to 17
7.Chinese Algae EaterGyrinocheilus aymonieriUp to 11
8.Rubber Lip PlecoChaetostoma milesiUp to 7
9.Snowball PlecoHypancistrus inspectorUp to 6.3
10.Bristlenose PlecoAncistrus cirrhosusUp to 6
11.Zebra PlecoHypancistrus zebraUp to 4
12.Dwarf SuckermouthOtocinclus vittatusUp to 2

The photo featured at the top of this post is © Ictiologia Universidad Católica de Oriente/Wikimedia Commons – License / Original

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About the Author

Lev is a writer at AZ Animals who primarily covers topics on animals, geography, and plants. He has been writing for more than 4 years and loves researching topics and learning new things. His three biggest loves in the world are music, travel, and animals. He has his diving license and loves sea creatures. His favorite animal in the world is the manta ray.

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