Algae Eater Fishes For Small Tanks: Everything You Need To Know

Algae growth is a common issue that any aquarium owner has to face. Some algae can be normal and healthy, but excessive growth can overrun a small tank and cause harm to fish or plants.

But before deciding to go for toxic algae-removing chemicals, it’s best to seek algae eaters, those with expertise in algae removal and who are naturally safe for the tank’s populations.

So if you’re looking for perfect algae eaters for your small tanks, keep reading to find the 10 favorite options for nano conditions and some relevant information to pick the most appropriate species for your tanks.

What Is An Algae Eater?

Algae eaters sometimes called “a clean-up crew” is a common term for describing large fish and invertebrates that feed on algae.

Algae eaters can clear algae before it overruns the tank and keeps the algae under control without harsh chemicals. Hence, they have long been a crucial part of the aquarium hobby due to their ability to balance the natural ecosystem.

How To Select The Most Appropriate Algae Eaters For Small Tank

When choosing algae eaters for a small tank, the most important thing is to consider their size. Unfortunately, some species that reach more than 10 inches seem not compatible with nano tanks.

Furthermore, you should also think about their personalities and specific requirements for your tank. Then, depending on the type of algae growth, the advice is to pick an algae eater that feeds on the specific type of current algae in the aquarium.

Besides, it’s better to consider the tank’s conditions. Algae eaters have their own needs for tank parameters, so it’s vital to choose the suitable species for your tank’s conditions.

Otherwise, change your tank’s conditions. But fortunately, most commercial algae eaters in the market can grow within a variety of water parameters. So make sure to keep the water clean, and the different personalities of the aquatic habitats match together.

Last but not least, remember to choose an algae eater that suits your tank care routine. For example, some species often need more attention or supplemental feeding than others. In that case, it’s essential to add vegetables or algae wafers and pellets to the algae eater.

Algae Eaters Vs Chemicals

Since algae can quickly overrun a small tank, several alga-removing chemicals are often used to deal with the problem. Although chemicals can be effective at some points, they tend to cause more harm in the long term because they contain several toxic ingredients that destroy algae blooms and even live plants.

Besides, they can accumulate in the water and negatively impact the aquarium. Hence, do not use algae remover chemicals at all costs.

Instead, opt for algae eaters, so fish and invertebrates do not get poisoned. They are a much safer option due to the ability to remove algae naturally without intervening with other live plants and fish. Some can also be grouped in a tank for an effective clean-up crew.

10 Best Algae-Eating Fish For Small Tanks

Siamese Algae Eater

Siamese Algae Eater

Siamese algae eaters are considered the most effective algae-eating fish because they can feed and control various types of algae, making them suitable for almost any tank. These fish can live in a 10-gallon nano tank and thrive at a temperature between 75°F and 79°F.

They consume some types of algae that are not flavorsome and are ignored by other algae eaters, such as the dreaded black beard algae. Also, these species are known for the ability to control flatworm citizens and leftover detritus in the tank.

Bristlenose Plecostomus ​

Bristlenose Plecostomus

Also known as the Bristlenose catfish, this small Plecostomus can only grow to a length of 3 or 4 inches, making them compatible with most medium-sized aquariums.

These species can handle algae perfectly and are easy to care for. They can tolerate a wide range of tank conditions but do well in a pH between 6.5 and 7.5. They require a minimum tank size of 20 gallons of driftwood, several hiding spots, and supplemental feeding with algae wafers.

Otocinclus Catfish

Otocinclus Catfish

These algae-eating catfish are one of the smallest species on the list. They can only grow to 2 inches or so. They are particularly effective at clearing brown algae and general new algae growth.

Caring for Otocinclus Catfish is relatively easy. They only require a tank of at least 30 gallons and a pH between 6.5 and 7.5.

Twig Catfish

Twig Catfish

They have long, thin bodies and grow well in nano environments. They do an excellent job of clearing a tank of green algae and can reach algae in narrow spaces.

However, they require special care since they do not adapt to water chemistry. They should be kept in a tank of at least 12 gallons, with high oxygen levels and a pH level between 6.0 and 8.0. Also, they need a place to hide in the tank due to their shy personality.

Florida Flag Fish

Florida Flag Fish

These fish are small, 2.4 inches in length and are distinguished with bright green, red, blue, and gold iridescent spots. They are among the few fish that feed on hair/thread algae and black beard algae.

Florida flag fish thrive in cool water community tanks between 70° and 85°F. But since they are known to jump, it is recommended to have a lid to cover the tank.

Hillstream Loach

Hillstream Loach

These species are typically small, reaching 2 to 3 inches on average. They are great at clearing away all the algae on the aquarium glass.

They can tolerate various water parameters but do well at 65-80°F. Although they can be semi-aggressive, they can be kept in a group of 3-4 to ease any aggression.


Mollies have a unique mouth feature to consume algae. In addition, they show their amazing ability to clear algae from surfaces.

They are peaceful fish and need to be kept in groups of six or more to live. On average, they can grow to 2-4 inches in length and prefer a tank of at least 20 gallons in size, with a pH between 7.5 and 8.5. But since they reproduce quickly, ensure the tank has enough space for them to fit in.


They are favorite algae eaters due to their colorful appearance and impressive ability to remove algae. Besides, they perfectly fit small tanks and can be kept in groups of eight or more.

Southern platyfish

Southern platyfish

These species look like mollies and have upturned mouths to graze algae. They can grow up only to 2.4 inches in length, allowing them to be compatible with nano environments.

Flying fox

Flying fox

Although these algae eaters can reach up to 6 inches, they have an average length of 3-4 inches, perfectly suitable for small tanks. In addition, they commonly feed on green algae, not the red species.

They can be kept in schools to cover a large surface in the aquarium, but it’s vital to keep an eye on them because they are highly aggressive and territorial.

Wrapping Up

Hopefully, you have found the most 10 options of algae-eating fish for small tanks. Depending on the size and conditions of tanks and the specific type of algae, you should choose the most suitable one for effective removal results. In addition, provide the algae eaters with appropriate environments and supplement feeding if needed.