You’re always battling algae if you own a freshwater tank. It’s just the way it is.
But you don’t need to fight that battle alone! In fact, adding one of the best algae eaters to your aquarium can make your job a whole lot easier.
While you’re at work, they’re cleaning. While you’re sleeping, they’re cleaning. While you’re trying to feed them, they’re still probably cleaning.
Algae eater fish and other similarly-motivated critters are more than just a luxury, they’re a smart investment in the health of your tank.
Here are some of the benefits they bring:
- A noticeable difference in water quality
- Less gunk and buildup for you to clean out
- Reduced wear and tear on your filtration system
We found ourselves recommending them all the time, so putting this guide together made a ton of sense. In it, you’ll see what species we consider to be the best algae eaters (fish, snails, and shrimp) for freshwater tanks with some helpful info about each.
Note: We’ve written in-depth care guides about many of these animals already, so if you want to learn more just click the links in each section!
Named after the whisker-like appendages coming out of their snouts, Bristlenose Plecos are docile algae-eating fish that can get along with most peaceful tank mates. They spend most of their time scavenging for different types of aquarium algae to snack on.
Despite their love for algae, Birstlenose Plecos can’t survive on natural growth in your tank alone. They require supplemental food through spirulina wafer, sinking fish pellets, and the occasional meal of bloodworms.
Reaching a maximum size of about 5 inches, these Plecos need ample room to roam. They need a tank that’s at least 25 gallons in size, though more is always welcome.
As for environment and water conditions, Bristlenose Plecos are very hardy. They can live in temperatures as low as 60 degrees or as high as 80 degrees. A pH balance between 6.5 and 7.5 is required to stay healthy as well.
In large groups, Cherry Shrimp can do a lot to manage algae levels in your tank. These tiny shrimp are a valuable addition to a freshwater ecosystem and will spend their days eating moss and as much algae as they can stomach.
Known for their vibrant red coloration, Cherry Shrimp stand out amongst the natural backdrop of a lush tank. Unfortunately, that makes them the target for predatory fish. The shrimp are peaceful by nature and do best with other like-minded fish.
Cherry Shrimp are without a doubt one of the best algae eaters around and are relatively easy to care for. They don’t require strict water conditions and can easily adapt to any environment. They can thrive in temperatures as high as 85 degrees and will often reproduce quicker the warmer the water gets.
pH balance should be kept between 6.5 and 8.0. As for space, a sizable group of 2 to 4 shrimp will only need a 10-gallon tank to stay happy.
3. Trumpet Snail
These tiny little snails have a short lifespan. While they only live for a year, most of that time will be spent chowing down on algae throughout your tank. Because they don’t get any bigger than an inch in length, Trumpet Snails can get into the tightest spots in search of food.
You can often find them sneaking around rocks, climbing up plants, and even burrowing in the substrate. Thanks to their conical shells, Trumpet Snails are more than capable of uprooting plants, so exercise caution when arranging your tank!
Another important thing to be wary of is breeding. Like many other freshwater snails, Trumpet Snails reproduce at a very rapid pace. The population can quickly take over your tank if you don’t have population control measures in place.
4. Whiptail Catfish
Whiptail Catfish are hardy creatures that prefer warmer waters. They do best in temperatures between 72 and 79 degrees. As for water acidity, these algae-eating fish prefer relatively neutral habitats with a pH balance between 6.0 and 7.5.
This species of catfish offers a unique look. They’re covered in shades of tan and black, which easily blends into the substrate. Their bodies are covered in thick scales that offer significant protection, much like armor on a knight.
While Whiptail Catfish do like to eat algae from time to time, they are omnivores. They lean more toward protein when given the chance. In between snacking on algae, they will feed on uneaten fish food, frozen foods, and even live foods packed with protein.
These invertebrates are aptly named for their sudden growth spurts. When they are purchases as juveniles, Mystery Snails are quite small. However, in the span of a year, they can reach sizes of 2 inches in diameter. Some will even get as big as a baseball!
They come in a wide range of colors. Most often, these snails take on a bright yellow hue, making them easy to spot in your tank. You can find them feeding on all types of algae. This includes green plant algae, algae in the substrate, and algae on the glass.
Mystery Snails are highly adaptable creatures. They can stay healthy in temperatures ranging from 68 to 84 degrees. Slightly alkaline water with a pH balance between 7.6 to 8.4 is best.
6. Amano Shrimp
While they are technically part of the “Dwarf Shrimp” family, Amano Shrimp can get up to 2 inches in length. Their bodies are gray and semi-transparent. Some specimens even have splashes of blue, which complements the dark spots that cover their body.
Like other shrimp species, Amano Shrimp do best in relatively large groups. A 10-gallon tank is required. It’s recommended that you provide an additional 2 gallons of space for every shrimp in the tank. Though, the low biomass these critters produce makes it nearly impossible to overcrowd a tank.
They prefer a pH between 6.5 and 7.5 as well as temperatures between 72 and 78 degrees. Even though they’re some of the best algae eaters you can get (they prefer green algae by the way), you might spot them chowing on some leftover fish food or other detritus as well.
7. Nerite Snail
Nerite Snails are some of the best algae eaters out there, and only get to be about an inch in size. However, they have beautiful striped shells that you can’t miss. Because they are so small, you only a 10-gallon tank to support them.
These snails are not hard to care for. This is especially true when it comes to water quality. They do best in moderate conditions with temperatures between 72 and 79 degrees. The pH balance can be anywhere from 7.0 to 8.5.
The cool thing about Nerite Snails is that they eat almost any kind of algae. This includes green spot algae, which is notoriously tough for other species. The snails can survive on algae alone, though you might want to introduce an algae wafer if you don’t think your snail is getting enough food.
Siamese Algae Eaters are a great tank-cleaning fish that work hard to keep things looking spotless. They consume all kinds of algae. The fish will even gobble up types of algae that other creatures ignore.
Measuring about 6 inches in length when fully grown, Siamese Algae Eaters are a beautiful ornamental fish that also serves a practical purpose. They’re covered in beige and have a prominent horizontal stripe that runs along the entire length of their body.
These algae-eating fish are very peaceful. They get along well with other non-aggressive fish species, as they’ll spend most of their time preventing algae from taking over the tank.
A slightly larger tank of 25 to 30 gallons is recommended. Temperatures should be kept around 75 to 79 degrees while the water’s pH needs to stay between 6.5 to 7.0.
Hailing from South America, the Rubber Lip Pleco is a bottom-dwelling fish that can keep your tank in good shape for years. They have a long lifespan of up to 12 years! During that time, they’re capable of reaching lengths 7 inches.
When it comes to behavior and temperament, Rubber Lip Plecos are quite solitary and will not pay other fish any mind. They’ll spend all of their time at the bottom of the water column sucking on algae to feed.
The minimum tank size you need to keep these fish is 25 to 30 gallons. Temperatures should stay between 72 and 80 degrees. Meanwhile, the pH should be around 6.5 to 8.0.
Like other large plecos, algae can’t be the only source of nutrition for the fish. Plant-based foods, such as algae wafers and green vegetables will provide the balanced diet they need.
10. Ramshorn Snail
Ramshorn Snails are another tank addition that has definitely earned their place among the best freshwater algae eaters. They aren’t too picky when it comes to the type of algae they eat. You might also see them feeding on old fish food or decaying plant leaves.
Unlike other snails, Ramshorns typically don’t eat plants when they are well fed. That said, they might turn to plant leaves if algae aren’t giving them the nutrients they need to stay healthy.
There are several color variations for Ramshorn Snails. However, all of them feature that iconic ram’s horn shell, which looks like a flat coil of rope.
You don’t need a huge tank to raise these snails. 10-gallons is the minimum. Though, we recommend larger if you plan on keeping a large group of them together.
11. Bamboo Shrimp
As one of the larger algae-eating shrimp species available, Bamboo Shrimp require slightly larger habitats to thrive. We recommend sticking to tanks no smaller than 20 gallons. That’s for a single full-grown shrimp of 2 to 3 inches. If you have a group, increase the size of the tank significantly.
The pH should be around 6.5 to 8.0 while the temperature can be anywhere between 70 and 78 degrees.
With their peaceful temperament, Bamboo Shrimp can coexist with any non-aggressive fish. They can even live comfortably with small fish without any issues.
These invertebrae will primarily eat algae and plant matter. You can supplement this meal with some wafer or green vegetables but do so with caution. In most instances, you will not need to intervene in their eating habits at all.
Not to be confused with the Siamese Algae Eater, this fish is one of the only few algae-eating species that you can keep with semi-aggressive fish. Chinese Algae Eaters can get up to 10 inches long. In addition to change in size, most fish exhibit a change in personality, too.
They are known to get more aggressive as they age. This can be beneficial. When you factor in their large size, the semi-aggressive behavior ensures that they can fend for themselves against other large and aggressive fish.
Chinese Algae Eaters need at least 30 gallons of space with a pH of around 6.5 to 7.5 and a temperature between 74 and 80 degrees.
Typically, Chinese Algae Eaters spend their time at the bottom of the tank searching for algae to eat. As a result, you need to decorate the bottom of your tank with fine sand, lots of plants, and more.
13. Rabbit Snail
Named after the long antennae that extend out of their heads, the Rabbit Snails are a large algae-eating invertebrate that you can add to your freshwater tank. When fully grown, these creatures can get up to 5 inches in diameter. They have long conical shells that are typically colored with black, brown, and white.
At the very least, Rabbit Snails need a 30-gallon tank. They prefer temperatures to be in the range of 76 and 84 degrees. Water should be fairly neutral to prevent shell erosion.
Unlike other snails, you don’t have to worry about overpopulation. These critters will reproduce in your tank, but the process is much slower and far more manageable.
A typical day in the life of a Rabbit Snail consists of eating algae, dead plant matter, and other detritus. The only live plants they have been known to eat are Java Fern.
At first glance, it’s easy to mistake Otocinclus for juvenile Chinese Algae Eaters. However, they are a completely different species. They only get to be about 2 inches long and are much more peaceful.
They are covered in splotches of beige and brown. Running through the center of their body is a thick black stripe.
Algae is their main source of food. This tank-cleaning fish has a healthy appetite for brown algae. In fact, they have been known to eat it quickly, which helps to prevent the algae from becoming a major problem.
Otocinclus can eat other foods, too. They appreciate the occasional algae wafer or green leafy vegetables.
These are easy-going algae-eating fish that aren’t too picky about the environment. They need a 30-gallon tank, a pH balance of roughly 6.8 to 7.5, and temperatures between 72 and 79 degrees.
Found throughout rivers in Florida, the Flagfish is a colorful species that has a penchant for chowing down on algae. These fish aren’t very big. They only get to be about 2.4 inches in length.
However, they have a girthy body shape and shortened snout. The Flagfish gets its name from its colorful appearance. Stripes of iridescent red, blue, and green create a passing resemblance to the American flag.
While they are omnivores, Flagfish does like to eat algae and plant matter. No matter how big your tank is, algae alone won’t cut it as a full diet. Luckily, these fish will happily take standard fish flakes, live food, and pretty much anything else they can get ahold of.
16. Twig Catfish
Twig Catfish are some of the most distinct-looking freshwater algae eaters available. They have grown very popular in recent years. However, they can be a bit challenging to care for.
Generally, these fish are quite peaceful and do just fine with other docile species. That said, they can get very skittish. They need plenty of good hiding spaces in their tank to feel safe.
Speaking of the tank, Twig Catfish need at least 35 to 40 gallons. They get to be 4 inches in length. But, they must be kept in pairs to stay happy. A 40-gallon tank is perfect for a pair.
This species is sensitive to water conditions, so do your best to keep temperatures between 73 and 79 degrees and pH around 6.5 to 7.5
Twig Catfish are master scavengers. They’ll pick off and eat algae from any surface they can.
17. Sailfin Pleco
If you’re looking for a behemoth algae eater, the Sailfin Pleco may be for you. It can reach lengths of more than 19 inches! Though, 11 to 13 inches is the average for fish in captivity.
Because they are so large, you’re going to need a massive tank. At the very least, they need a 100-gallon tank. More is preferred, as they need some room to swim around.
When it comes to temperature, these algae-eating fish can adapt to nearly anything. As long as it’s within a reasonable range, the fish should be fine. However, pH requirements are a bit more strict. They require levels between 6.5 and 8.0.
Algae is the food of choice for Sailfin Plecos. They particularly enjoy algae that’s on driftwood. Not only does driftwood continuously produce algae, but the cellulose in the wood can also improve the digestive system of the fish.
18. Ghost Shrimp
Also known as Glass Shrimp, this invertebrate will almost exclusively feed on algae. They may also consume some organic plant matter, but algae are their main dish.
Ghost Shrimp are relatively small, reaching lengths of about 2 inches when fully grown. As a result, you only need a 10-gallon tank to keep them healthy. Many aquarists prefer larger tanks to keep a large group together, which can do wonders for keeping algae under control.
Preferred temperatures are 68 to 85 degrees. The pH balance should be stabilized around 6.5 to 8.0.
Like most shrimp, Ghost Shrimp are very peaceful scavengers. They’ll stick towards the bottom of the tank and occasionally climb plants to feed. They can be kept with non-aggressive community fish.
Mollies are a very popular livebearing fish that’s been known to snack on algae every once in a while. They aren’t exclusive algae eaters, so you’ll need to provide them with standard flakes or pellets to supplement their diets.
These fish come in a wide range of colors and patterns. As adults, they are about 4.5 inches long. Mollies are known to reproduce very quickly, so be wary about your tank size.
A single pair can do just fine in 10-gallon tanks. Though, 20 gallons is preferred so that they have ample room to roam. As they breed, you’ll need to increase the tank size to accommodate for the new fish you’ll have around.
The preferred temperature for Mollies is a moderate 72 to 78 degrees. Meanwhile, the pH should be on the alkali side. Around 6.8 to 8.5 is ideal.
20. Doctor Fish aka Red Garra
Whether you call them Doctor Fish or Red Garras, these fish are born to eat algae. They thrive on biofilm and algae that’s on rocks, driftwood, and plants. That’s not all they’ll eat.
You might have seen these small silver fish being used in spas and clinics. They will eat dead skin cells right off a person’s body!
Of course, they won’t have access to all of that in an aquarium, so algae will have to do. You can supplement the algae with dry or frozen food. Despite their appetite for algae, they do appreciate protein-rich foods every once in a while.
Doctor Fish grow just shy of 5 inches as adults. If you plan on keeping a small group of them together, you will need a tank that’s at least 30 gallons in size.
Temperatures can be on the cooler side. They prefer cool waters between 57 and 68 degrees. As for pH, keep things relatively neutral.
Now It’s Time To Pick Your Favorite!
You can’t go wrong with any of the best algae eaters. Whether you’re looking for a fish, shrimp, or snail, the species above will get the job done.
There’s something about watching these critters work that’s oddly inspiring. They stay focused and consistently track down algae no matter what’s going on.
If something disturbs them, they’ll wait it out and get right back to work. They can’t be stopped!
If you have any questions about other algae-eating fish or want to learn more about the species we included, don’t hesitate to get in touch with us on social media. We love connecting with other aquarists and swapping stories.