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Do Tilapia Eat Algae? (What You Should Know)

Do Tilapia Eat Algae?

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Centuries ago, experts believed that algae were part of the Plantae kingdom. Their observation is understandable because, like plants, they can photosynthesize, and some algae like seaweed do resemble them. While algae play a beneficial role in an ecosystem, an excessive amount of these organisms in a fish tank can wreak havoc on water conditions. Others recommend adding algae-eaters like fish to contain this issue. Thus, if you already have tilapia in your system, then you surely want to know, do tilapia eat algae?

The tilapia an omnivorous fish eat microorganisms such as algae. Tilapia thrive on eating smaller animals, plants, bacteria, and algae since they can obtain nutrients from them. And to fully understand this matter, we will examine algae and how the tilapia fish can control this organism’s growth. In this article, we will discuss the microorganism algae, their effects in an ecosystem, and tilapia as algae eaters.  

What Are Algae?

Surprisingly, when we say algae, the word is not exactly a specific term. To be precise, algae pertain to a variety of organisms. The three diverse types are cyanobacteria, microalgae, and macroalgae. Nearly all of these groups photosynthesize, although others may not have the ability anymore. 

Their ability to photosynthesize allows them to generate nutrients utilizing sunlight and carbon dioxide to produce oxygen and carbohydrates. While this trait is highly useful in an ecosystem, the widespread growth of algae can disturb the balance of your water condition. Here are a few types of algae you may encounter in your system:

Hair Algae

As their name suggests, hair algae look similar to long, slender, strands of hair. They appear in shades of brown, black, and green types that emerge in various conditions. Generally, an oversupply of light, nutrients like iron, or lack of them can trigger these algae. This variety is tricky because they develop swiftly and are tough to eliminate. 

Brown Diatom Algae

One of the most natural algae to contain are brown diatom algae. Although they sometimes appear green, this organism looks like a flour-like material coating fish tank walls and floors. They are light and straightforward to rub off, so aquatic animals enjoy eating them. The brown diatom algae are often seen in new fish tanks with a steep concentration of silicates and phosphates. 

Green Spot Algae

The green spot algae appear as small spots on the walls of fish tanks. There are several reasons for their outbreak, like discrepancies in phosphate levels or prolonged exposure to sunlight. When getting rid of green spot algae from your tank wall, make sure to use a scraper, which is glass or acrylic safe.  

Blue-Green Algae

On the other hand, blue-green algae are cyanobacteria that resemble a thick blanket that covers the fish tank. These algae give out a prominent smell that aquatic enthusiasts readily identify before bacterial growth is noticeable. At the moment, experts have yet to trace what triggers blue-green algae. However, proper routine maintenance and adequate water circulation will prevent the growth of this organism.  

Green Water

If your fish tank is looking like a pea soup these days, you are potentially facing green water. The problem occurs due to an overgrowth of single-celled phytoplankton. Even with significant water changes, it will be a challenge to flush these organisms because they recreate rapidly. An increase in ammonia, too much lighting, and excessive nutrients can cause green water. 

Effects Of Algae In Aquaponics

Effects Of Algae In Aquaponics

As mentioned before, similar to plants, algae produce oxygen. Their presence in the fish tank boosts the water’s dissolved oxygen levels, which is crucial for the fish.  Also, together with the beneficial bacteria, they lessen the traces of hazardous nitrogen in the system. 

However, an abundance of these microorganisms can be risky in terms of the safety of your setup. Though algae produce oxygen during daylight, they likewise consume them at night. Hence, when there is an accumulation of algae, it will reduce dissolved oxygen. 

Furthermore, an overgrowth of algae can cause variation in pH levels. Since they photosynthesize during daylight, they absorb carbon dioxide. Once there is a shortage of this chemical, the water becomes alkaline or basic, which can harm your fish. 

Do Tilapia Eat Algae?

A practice most gardeners observe when controlling algae growth is to add algae eaters in their fish tank. Fish that are omnivores are a practical choice since they consume these types of organisms. If you are already raising tilapia in your system, you are lucky because these fish eat algae. 

Most of the tilapia variety are omnivores. However, the common ones known to thrive on algae are the Nile and Blue tilapia. They still consume other small animals; however, they mostly feed on phytoplankton and algae. 


Yes, tilapia eat algae. The resilient omnivore fish, though known to consume meat, also thrive on eating these organisms. While algae can play an essential role in an ecosystem, rampant growth could be detrimental to your unit. 

Problems such as decreased oxygen levels and pH fluctuations can occur when growers do not contain this issue. Since utilizing chemicals is not an option for aquaponics, adding fish like tilapia that consume algae is economical and a better alternative. If you want to know if tilapia breeding is right up your alley, click here.

The Campbells love finding sustainable and fun ways to increase their independence from traditional brick and motor supermarkets. Aquaponics provides a full lifecycle food source for families and a great hobby. #aquaponicslifestyle

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