Does Freshwater Coral Exist?

Several reefs around the world contain only saltwater corals need to survive, but we’re curious if freshwater corals exist. Sadly, they don’t. 

Corals are an interesting species that continue to generate much awe from mankind. But why do these beautiful creatures find it difficult to thrive in any body of water with low salinity?

Several reasons abound why corals only live in water bodies high in salts. 

In this guide, we’ll get to see more information about corals and find out if they can survive in freshwater. 

Does Freshwater Coral Exist?

Do Freshwater Corals Exist?

Live corals in freshwater remain a myth, as no one has ever discovered these organisms living outside saltwater. 

The closest you can get to a freshwater coral are bryozoans – calciferous, skeleton-like creatures. Bryozoans live in a colonial format and branch in a similar pattern to LPS corals. 

These organisms can survive in freshwater and are favorites for hobbyists looking to place a coral in their fish tank. 

Can Corals Survive in Freshwater?

Freshwater has a higher acidic content than seawater and is a major cause of coral bleaching and death. Freshwater causes corals’ cells to burst upon constant exposure to freshwater. 

Can You Add Corals to a Fish Tank?

Adding corals to a fish tank is possible, but has to be monitored by an expert to avoid causing problems. Putting too much coral may cause several health challenges for fish in a freshwater tank. 

What Happens When Corals are Added to a Freshwater Tank?

Altered water chemistry 

Crushed corals are usually added to freshwater containing fish to raise its pH level. But in most cases, such additions are done gradually to avoid drastic changes to your fish’s water chemistry. 

Putting a live coral into a freshwater tank can drastically change the water’s pH and change its hardness levels. Sudden changes to your freshwater tank’s pH could prove fatal for the fish inside it. 

Ammonia & nitrite spikes

Live corals placed in a freshwater tank alter the water’s chemical composition and does much more. Harmful spikes in nitrite and ammonia will occur, as live corals will die when placed in a freshwater tank. 

Compromised immunity against diseases

Unstable chemical compounds from live corals can cause stress to your fish’s immune system. Stressed fish become more prone to diseases and become easy targets for parasites and bacteria in its tank. 

Ideal Water Quality to Set Up Corals’ Aquaria

Owners of a reef aquarium must consider its water quality at all times to avoid killing aquatic life. Adding corals to your reef aquaria makes it more difficult to maintain, as more parameters need monitoring to guarantee safety. 

Here’s a look at most common parameters necessary to set up an aquaria for corals:


Corals can only survive in precise temperatures within 75° – 80°F. You need to use an aquarium thermometer to monitor your reef aquarium’s temperature. 

Ensuring the correct temperature makes sure your corals and aquatic life do not decline in number. 

Magnesium content

Reef aquaria should have a high amount of magnesium to boost interaction with alkaline salts and calcium. Corals need calcium and magnesium to develop their skeletal structure. 

Most seawater have a magnesium level around 1300pp. Adding synthetic salt for reefs is enough to provide the magnesium your corals need to thrive. 


According to this study, reefers must monitor ammonia levels and make sure it remains well below 0.1ppm. Adding corals to an aquarium with high ammonia levels puts your fish at risk.

It’s easy to keep ammonia levels low with a functional bio-filter. 


Phosphates affect coral skeleton growth and must be kept at very low levels in a reef aquarium. These salts must remain below 0.03ppm in a tank containing corals. 

Growing and removing macro-algae from your corals’ tank is a smart way to reduce phosphate levels. You can also use a phosphate binder, feed your fish low-phosphate foods, or use a protein skimmer to reduce phosphates.

Trace compounds

Corals require trace amounts of compounds like strontium, boron, and iron in their habitat. Testing for these compounds may be difficult, especially without special equipment.

The best way to maintain these compounds’ presence in reef aquaria is by scheduling regular water changes and reef salt additions. Consulting someone with experience about reef aquariums can help you get an accurate measure of reef salt and water-changing timelines. 


Several scholars have claimed few lakes around the world have freshwater corals. But extensive research always proves this to be false. 

Freshwater corals remain a myth, even with several bacteria-like organisms mimicking their presence in salt-free waters. 

So, if you’re looking for a freshwater coral to add to your aquarium, it’s best to choose an artificial one. Several companies produce life-like corals that can feature in any tank and look like the real thing. 

The only way to have live corals in your tank is to use a reef tank or add saltwater to your aquarium.