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Aquarium-Cleaning Fish

I've always had an interest in aquariums, aquaponics, and interconnected farming systems. I'd love to share what I've learned with you.

In order to keep your aquarium clean, you need to add some algae-eaters to your tank to make sure that the algae doesn't spread too much.

In order to keep your aquarium clean, you need to add some algae-eaters to your tank to make sure that the algae doesn't spread too much.

Algae is a normal part of any aquarium ecosystem, but it has to be kept in small quantities for other living things to thrive in the same environment. That's why you need to add some algae-eaters to your tank to make sure that the algae doesn't spread too much.

Snails and shrimp eat algae, but we will now take a closer look at some of the most popular algae-eating fish species that you can find in almost any pet store. Get a few and make sure that your tank stays as clean as possible.

A Siamese Algae Eater

A Siamese Algae Eater

Siamese Algae Eater

The Siamese algae eater eats the most algae of all similar species of fish. These fish are beautiful to watch as they clean the aquarium from algae for hours on end. Even though their primary food is algae, they will also eat leftover food, live food, flakes, and even vegetables.

When it grows up, the fish reaches about two inches in length. It's a relentless algae eater, ideal for all tank sizes, and it doesn't attack other fish or animals. They can, however, attack members of their own species if there are too many in the same tank. That's why you should keep their numbers to a maximum of about 5 fish per 100 liters.

It doesn't take a lot of effort to care for Siamese algae eaters, but they need a steady stream of oxygen to thrive. The ideal water temperature for this species is 77° F. Since these fish are very territorial, they need plenty of space to swim, and they like a lot of plants and leaves in their surroundings. You should know that the Siamese algae eaters are known to jump out of the water, so it's best that you put a lid over the tank. They are a fun species that will be a welcomed addition to your aquarium.

Twig Catfish

Here we have a fish with a long, thin body that reaches up to four inches in length. The twig catfish got its name because it resembles a twig. It's a peaceful species that doesn't attack other fish, but it can be bullied by larger fish. The species used to be hard to find, but not anymore because of the many hatcheries that breed them in massive quantities.

You'll need at least a 12-gallon tank for this fish. They usually live in pairs, and they need a pH level of between 6.0 and 8.0. Also, twig catfish are very sensitive to water chemistry changes. Although they like to eat algae, you'll have to provide some supplemental feed. They like hiding in caves and under reefs, and they require some extra effort and care.

A Bristlenose Plecos

A Bristlenose Plecos

Bristlenose Plecos

The bristlenose pleco is a fish that really likes to eat algae. It can grow up to six inches in length, and it has a sucker mouth that can cover a lot of ground and eat a lot of algae. They are bigger than most algae-eating species, so they will need supplemental algae pellets because they will eat all of the algae in the tank in no time.

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A unique fact about this species is that it eats green spot algae, which is something most other algae eaters tend to stay away from. Since they have a massive appetite, and they're not picky eaters, it's clear why they are one of the best and most popular algae-eating species.

They are good neighbors and won't attack other fish in the tank. You won't be able to see them swim around a lot during the day, as they usually feed at night. Even so, they like to stay out of trouble and hide in the rocks. You can introduce them to the same tank with larger fish without worrying about them getting eaten.

Otocinclus Catfish

Some algae eaters are very small, and that's the case with the Otocinclus catfish. It grows to a maximum of two inches, which puts it among the tiniest algae eaters of all. You can easily mix them with Chinese algae eaters, but the most significant difference is in their attitude. This species is very peaceful and doesn't attack other fish.

Otocinclus catfish like spending time around other bottom feeders, but they don't do well with larger or aggressive species. You won't have to spend a lot of time or money to integrate them into your tank since they are effortless to look after. Your tank has to hold at least 30 gallons because they need a lot of algae to survive. They live in schools, so you'll need to introduce more of them at the same time.

Their ideal pH levels are between 6.5 and 7.5, but they don't mind sudden changes in water chemistry. You should get several Otocinclus catfish if you have too many brown algae, their favorite food.




Mollies are not the hungriest algae eaters on the list, but they will sometimes feast on algae. They are unique because they give birth to live young. The species is very peaceful and does well in community tanks with a minimum of 20 gallons. Mollies grow up to four inches and thrive in water pH of 7.5 to 8.5.

Furthermore, mollies like brackish conditions, so you can add a bit of salt to your tank, as long as the other species can handle it. However, this species reproduces at a really fast rate, so you'll need to keep an eye on their numbers to prevent the tank from becoming too crowded. They come in different colors, so you know they will look great in your tank.

Let the Fish Do the Cleaning

Sometimes it can be a bit hard to look after your fish tank, especially if you don't have any algae-cleaning fish or snails. You’d have to change the water at least twice a month, and that's often easier said than done. So, help yourself by getting a few algae eaters that will keep the water clean for longer. Bristlenose plecos can never get enough algae, but the other species we've selected are also beneficial. Select the ones you like the most and introduce them to your aquarium today.

This content is accurate and true to the best of the author’s knowledge and is not meant to substitute for formal and individualized advice from a qualified professional.

© 2019 Ben Martin


Steve from Chingford London on June 12, 2020:

Been keeping fish since 1976 you never stop learning.recently, I started with shrimp. Something I never did before. Having been through just about every fish going almost, starting afresh with these great little critters is fastinaing. And there again there's so much to learn. You might say it's revamped the hobby for me. So I'll be posting questions a plenty I reckon..

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