When you buy through links on our site, we may earn an affiliate commission at no cost to you.

The Bottom Feeders That Should Be At the Top of Your List – The Siamese Algae Eater

The algae eater is the quintessential addition to any aquarium tank. While you may find yourself getting caught up in the sheer number and choices available to you as you begin your fishkeeping journey, one thing is obvious: you need a way to keep your aquarium clean and healthy for years to come.

The easy solution? An algae eater. These delightful creatures fill an important role in your tank’s environment, helping to tidy up tanks by munching on algae wherever they happen to spot it.

These fish are active and social, performing well in large groups as well as when housed by themselves. They are easy to feed and will eat just about anything that you put in your tank – but they especially love algae of all kinds!

Algae eaters are peaceful and will get along with most fish in a community aquarium. The Siamese algae eater in particular is easy to care for and is a great choice for beginner and expert aquarium hobbyists alike.

Siamese Algae Eater 9


Siamese Algae Eater Background

Siamese Algae Eater 1

The Siamese algae eater, also known as Crossocheilus oblongus, is a freshwater fish species from the Cyprinidae family. This family also contains carp, and so they are close relatives of each other.

These fish originated in southeast Asia, hailing from the wilds of Malaysia and Thailand. However, you can now find Siamese algae eaters in just about every country in the world as they are bred prolifically for the aquarium trade. These fish are some of the best algae eaters you can find. They move around frequently and can clean your entire tank in a matter of minutes.

In the wild, Siamese algae eaters are found in densely vegetated streams and large rivers. They live nearby and in the same fashion as Asian carp. The tropical waters in which they are found are usually somewhat acidic, and tend to have a very slow-moving current. They hang out among rocks, logs, and plants. They will spend their time among these shelters, alternately hiding and scouring the surfaces for food.

In their native environments, Siamese algae eaters will mostly consume algae, but they will eat anything that sinks to the river bottom. They don’t like to roam and instead will stay around familiar shelters, rarely venturing up to the surface of the water.

You can find Siamese algae eaters at just about any pet store. They are so popular that they are very easy to find. They are also incredibly affordable, with prices starting at just $3 to $5 per fish. The Siamese algae eater is an excellent choice for a beginner, as it can keep your tank clean and presents minimal disruptive behaviors to your tank environment. Keep in mind, though, that like other fish, Siamese algae eaters do produce a significant amount of waste. You’ll want to avoid overcrowding for this very reason.

These fish are often confused with a similar species, the Siamese flying fox. Although they look similar, they are different species with different care requirements. The Siamese algae eater will have a longer black stripe that stretches to the end of its tail fin. While the Siamese flying fox also has a black stripe, it is smoother and ends right before the start of the tail fin. The Siamese flying fox will also have flaps near the corner of its mouth.

Siamese Algae Eater Appearance And Behavior

Siamese Algae -Eater 2

This species of fish has a unique appearance that distinguishes it from other algae eaters. It has a long, slender body that can span up to six inches in length. They can be either a light gold or gray color, but all fish will have a thick black stripe that reaches from the head to the tail.

This stripe sometimes fades. Most of the time, it is nothing to worry about, as it could simply be a mating display of courting. However, these stripes sometimes fade as a result of stress or illness, which you will need to minimize in the tank. Very rarely, the stripe will fade as the fish tries to camouflage itself – this is not very common in the aquarium setting but happens frequently in the wild.

There is little sexual dimorphism (or difference) between males and females. You usually will not notice these differences until they are about three or four years of age. Then, the only difference exists in the difference between the sizes of the fish – females will be somewhat larger than the males and may also have abdomens that are slightly more rounded.

Siamese algae eaters are bottom feeders, and so they will spend most of their time hanging out at the bottom of your tank. Very rarely will they rise to the middle or the top of the water column. Instead, they will swim around near the bottom sections of your tank until they happen upon a spot covered in algae. They will stay there until the algae is mostly gone.

If you keep several Siamese algae eaters together, they will form dense, close knit groups. They will feed together in the same area, even if there isn’t exactly enough algae to sustain them all!

These fish are very rarely aggressive, but they are extremely energetic. They like to dart around the tank in quick, rapid movements, and so while they won’t necessarily attack other fish, their presence can be disturbing to some calmer species.

Siamese Algae Eater Tank And Water Requirements

Siamese Algae Eater 6
Photo by Andrew

You should do your best to mimic the natural environment of the Siamese algae eater when you are setting up your tank. Remember that the water should be slightly acidic, and that you should include plenty of plants to keep the water clean and oxygenated.

Try to use a substrate that is fine and soft, such as sand, as this will make it safer to swim around near the bottom of the tank. Because Siamese algae eaters spend so much of their time at the bottom of the tank, there is a good chance that they can scratch their sensitive bodies or damage their barbels if you use a harsher, sharper substrate.

The water of your tank should be kept fairly warm. You will need a heater to keep temperatures within the ideal range, which is between 75 and 79 degrees Fahrenheit. The water hardness should be between 5 and 20 dH. These fish prefer slightly acidic waters, with a pH between 6.5 and 7.0, but they can tolerate a range. Try to keep it between 6.0 and 8.0 to ensure the health of your fish.

There are no specific requirements of this fish in regards to water flow or current, which may be astonishing as they are naturally found in rivers. While they prefer slower moving waters (the weaker the better), Siamese algae eaters really can adapt to most levels of flow within your tank.

The bigger the tank, the better when it comes to your Siamese algae eater. You can keep one fish per 20 gallon tank, but you should add an extra 10 gallons of space per every fish that you add.

Decorating A Siamese Algae Eater  Tank

Siamese Algae Eater 4

Plants and other decorations are critical in a Siamese algae eater tank for multiple reasons. The first is that they help to keep the water clean, but the second (and arguably most important) is that plants and other structures provide your fish with places to hide. This will help your fish feel safe and at home in your aquarium tank.

Your fish may start nibbling at plants if they are hungry. You can prevent them from doing this by maintaining an adequate feeding schedule, but you can also choose healthy and hardy live plants that will be able to hold up to the constant stress of the nibbling. Consider species that are quick to grow and rejuvenate, like hornwort, anacharis, or Java fern.

Providing plenty of structures in which your Siamese algae eaters can hide is also important. They need places to escape their tank mates, particularly if there are other bottom dwellers or somewhat aggressive fish. You can create caves around the tank, which will give your fish somewhere to escape. The Siamese algae eater is not territorial, so you shouldn’t have to worry about any fights related to these hiding places.

Siamese algae eaters can jump and are very active. While you might not notice or observe this behavior on a regular basis, there is always the potential for your Siamese algae eater to jump out of the tank. As a result, you should always keep a tight-fitting lid on the tank. This will ensure that you don’t have to deal with an escape artist – which could be potentially fatal for your fish.

What Do Siamese Algae Eaters  Eat?

Siamese Algae Eater 8
Photo by Vitamin G

As the name implies, Siamese algae eaters mostly eat – you guessed it – algae! However, in the wild these creatures eat a variety of foods. You might find Siamese algae eaters consuming vegetation, plant matter, and algae, as well as other items they find, like dead fish and insects. They are true omnivores, eating anything they come across or are able to scavenge.

As a result, they are easy to take care of in the aquarium. They are not picky eaters and will eat just about anything you choose to give them. Good choices include flake and pellet foods, as well live foods and algae wafers. While they can tolerate most live food options, good choices include brine shrimp and bloodworms. In addition to fresh live foods, you can also feed frozen food.

When you are feeding your Siamese algae eaters, remember that sinking foods tend to work best. They will fall past other fish that are hanging out closer to the top of the tank and will be able to make their way down to your bottom-dwelling algae eaters.

It can be tough to find a balance between over- and underfeeding your Siamese algae eaters. They will already be consuming algae and plants in the tank before feeding time, and it can be tough to tell how much they’ve actually eating. If you feed your fish too much, they will stop eating algae in favor of the foods you’re giving them.

These fish will gladly eat all day if you allow them, so try to limit feeding to just the amount that they can finish in a couple of minutes. You only need to feed them once a day, but you may need to feed your other fish more often than that. Keep that in mind as you develop a feeding schedule that will hopefully work for everybody in your aquarium.

Siamese Algae Eater Tank Mates

Siamese Algae Eater 5
Photo by David Midgley

Siamese algae eaters are friendly fish that get along with most other community fish. Since they spend most of their time at the bottom of a tank, you must consider who else will be living there. Some bottom dwellers can be aggressive or downright mean, so you will want to avoid fish like red tail sharks. These fish tend to harass and bully others in order to protect their territory – even members of their own species. Because algae eaters are more shy and not prone to conflict, they will spend most of their time swimming away and hiding from these aggressive species.

Otherwise, Siamese algae eaters are great candidates for community tanks because they are so peaceful and easygoing. You can choose peaceful bottom-dwellers like the Corydoras catfish, or you can select fish species that prefer to swim in the other areas of the tank. This will reduce the potential for any territorial disputes or problems.

Try to avoid adding fish that have a reputation for being aggressive, as they will attack or even try to eat your algae eaters. This is especially true when it comes to Siamese algae eaters that are young or are new to the tank. Avoid cichlids, who really should be kept in species-only tanks as it is, as well as other aggressive species like oscars.

Some fish species that have good potential for being members of a Siamese algae eater-friendly community include guppies, tetras, and danios. These fish are small and not aggressive. Other good choices include barbs and gouramis, who are large but do not behave aggressively.

You can even include non-fish species like cherry, amano, or ghost shrimp. You could even try out nerite snails. These organisms all eat algae, too, so you may have the opportunity to witness various algae eating behaviors as the animals interact with each other. They will add diversity and interest to your tank, while at the same time helping to keep it clean.

You can keep multiple Siamese algae eaters in the tank. These fish are unique in that they tend to school, so groups of four to six are best if you want to witness this schooling behavior. Just remember to increase the size of your tank when you add more fish, however, or you could have an issue of overcrowding on your hands.

That being sad, Siamese algae eaters do not have to be kept with other members of their species. You can keep them in pairs or as singles, which gives you plenty of options when it comes to how you want to populate your fish tank.

Keep in mind that one mistake people frequently make when raising Siamese algae eaters (particularly in multiples or in the presence of other algae eater) is that they assume that they do not need to clean the tank – ever. Remember, just because you have algae-eating species in the tank doesn’t mean they can handle the entire bioload themselves! They are still contributing waste and you will still need to put in an effort to keep your fish tank clean.

Common Siamese Algae Eater  Diseases

Siamese Algae Eater 7
Photo by Sato KGY

There are few diseases to which Siamese algae eaters alone are prone, but they can be affected by the same diseases that habitually affect freshwater tank species. Most diseases will give off clear symptoms so that you can treat them quickly, but others may present more hidden symptoms that can be harder to detect. Checking your fish on a daily basis can help you catch any problems early on – before they become life-threatening.

Ich is one of the most common disease in freshwater aquariums. This illness is caused by a parasite that creates small white dots around the body. You may notice  your fish rubbing itself against items in your tank as it attempts to “itch” itself. This can be prevented by conducted regular water changes. Dirty water is to fish as polluted air is to humans-  it does their health no good. Clean your tank once every two weeks to reduce the likelihood of toxins building up in the water and making your fish sick.

While you can purchase treatments to heal conditions like ich as well as other common bacterial, viral, and parasitic conditions, there is often no reason to – preventative care can be more effective than the most expensive medications. Keep your tank clean and only feed high-quality foods. Cheap foods – or foods that are fed at irregular intervals – can cause constipation and bloating. These issues can lead to organ dysfunction, too.

Be careful what (or who!) you add to your tank. Some decorations can carry toxins, and if you introduce water from other tanks (including the water from when you purchase new fish), this can also be dangerous. Whenever you add new fish to your tank, make sure you quarantine them first. This will help you to determine whether they are healthy before potentially introducing new diseases to your tank.

Breeding And Life Spans Of Siamese Algae Eaters

Siamese algae eater can be bred in the home aquarium, but it’s incredibly difficult to do. In order to be successful, you will need to use hormones, which is what the commercial farms do in order to supply pet stores with a steady supply of these fish.

Sexing the fish is particularly hard, as differences in the genders generally don’t appear until later in life. Although females are larger than males, they are only slightly larger, and this takes a keen eye to detect.

You can encourage spawning by altering water conditions to those they would experience in the wild during their breeding season. Besides this, there is little you can do to encourage breeding  – and there is little information available about individuals who have been successful in this attempt in the past.

Is A Siamese Algae Eater For You?

If you have a fish tank that is constantly filled with algae, don’t spend all your spare time cleaning it up. Instead, consider adding a Siamese algae eater to your tank. While these fish won’t take all the work out of caring for fish, they can certainly help lighten your duties and add some beauty and activity to your tank at the same time.

While they do require some attention and devotion to raise – you will need to make sure you provide a tank with a light substrate and plenty of plants – these hardy fish are a great choice for beginner and expert aquarium hobbyists alike.

Leave a Comment