Algae eater pond | What is an algae eater and how to prevent algae in the pond?
Algae can be a pest for pond owners and many of them would like to get rid of it. The pond fish: "the algae eater", solves this problem to some extent, but different types of aquatic plants also play an important role here. I am happy to explain more about algae and how to deal with and prevent it.
All about the algae-eater
- What is an algae-eater?
- How fast does an algae-eater grow?
- What are algae?
- How do I combat algae formation?
- Should algae eat anything besides algae?
- Can an algae-eater get along with other fish?
- What types of algae eaters exist?
What is an algae-eater?
The ancistrus, also known as the algae eater, is a fish especially suited for all kinds of ponds. As a bottom dweller, this fish feeds on plankton and various types of algae such as floating algae and filamentous algae. This is why the pond fish is also called an algivore. It is often thought that adding an algae-eater to the pond is the solution to algae problems. While the algae-eater can certainly help control algae, it does not completely solve the problem. This is because algae eaters can only consume a limited amount of algae.
How fast does an algae-eater grow?
In general, algae eaters grow more slowly in a pond than in the wild. In the wild, algae eaters can reach lengths of up to 60 centimeters. In a pond the algae-eater generally grows slower than in the wild, it can take several years in a pond before the fish will reach its maximum size. Therefore, it is possible to have a smaller pond for algae-eaters in the first few years.
Oxygen Plants
What are algae?
Algae are a group of unicellular or multicellular organisms found in both freshwater and saltwater. They can be either plant or animal, and they are often green in color due to their chlorophyll. Algae in a pond can have both positive and negative effects. On the positive side, algae can help break down waste products and help produce oxygen. They can also serve as a food source for pond animals, such as the algae-eater. But too much algae formation in the pond can lead to a green deposit on the water's surface that prevents oxygen plants from getting sunlight, from growing and therefore from releasing oxygen to the water which does not improve water quality.
Learn how to become a pond specialist for your pond
With the help of my books, stemming from 35 years of professional experience, discover how to save money in both the construction and maintenance of your pond.
How do I combat algae formation?
Algae formation can be controlled in part by placing an algae-eater in the pond, but of course it is even better to prevent algae. Algae can be prevented by pond substrate to the pond, substrate serves as a nesting place for beneficial bacteria. Furthermore, it is important to sufficient oxygen plants addition to the pond, these ensure that sufficient oxygen is present in the pond water and nutrients in the water disappear so that algae are not fed and thus can not expand. Furthermore, algae can be prevented by adding the right amount of good bacteria. Bacteria ensure that excess algae is cleared from the pond. When your pond is properly constructed and decorated there can be no excess algae formation.
Pond supplies
Should algae eat anything besides algae?
Algae-eaters cannot live on the intake of algae alone, they also need other nutrients such as algae-based food tablets and fish food. If there are other fish living in the pond, it is important to choose sinking fish food, because the algae-eater does not have good eyesight and thus needs some time to encounter the fish food on the bottom of the pond while swimming around.
The best fish food for the algae-eater
Can an algae-eater get along with other fish?
When algae eaters are young, they can live in groups or with other algae eaters. As they get older, they often become territorial and it may be necessary to separate them if they begin to fight each other. It is important to note that the ability to keep algae eaters in a pond or aquarium depends on the specific species. For example, the Siamese algae-eater differs somewhat from the "standard" algae-eater.
What types of algae eaters exist?
There are several types of algae eaters available, both for the aquarium and the pond. The following are some of the best-known species of algae eaters:
- Ancistrus: also known as the "bushynose" algae-eater, this fish has a flat nose and a body with small bristles and is suitable for in both aquariums and ponds.
- Otocinclus: a small algae-eater suitable for aquariums and known for its ability to climb up the sides of glass tanks.
- Chinese algae-eater: a popular species in the aquarium because of its unique appearance and ability to consume larger amounts of algae.
- Siamese algae-eater: this fish is known for its ability to consume both algae and leftover food, and is suitable for in aquariums.
- Plecostomus: a large and powerful algae-eater, suitable for in large aquariums and ponds. Plecostomus can grow up to 60 centimeters long.
It is important to understand the specific characteristics and requirements of each species of algae-eater before choosing one to keep in your aquarium or pond.
Frequently asked questions about algae eaters
As algae eaters grow older, they may begin to exhibit aggressive behavior toward each other. In the first years of life this is often not yet the case. When you notice that the algae eaters start showing aggressive behavior, it is important to separate them from each other.
Because an algae-eater is a tropical species of fish, they cannot simply be placed in cold water. Most algae eaters need a water temperature between 18-24 degrees.

Simon van der Velde
Pond specialist and aquatic plant grower since 1986
Simon's vision is to let nature do its work in your pond. No need to buy all kinds of measuring equipment and water improvers. If the fish are swimming nicely and the plants are growing well, then the water in the pond is of good quality. With a good planting plan and the right approach, you can save a lot of money and maintenance, and ensure a clear, biologically balanced pond that becomes more beautiful every year.