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Can Saltwater Crabs Live in Freshwater? (Read This First!)

Crabs fall in the category of crustaceans. Their sizes vary as it ranges from small to medium. Crabs mainly reside in the salty water of the ocean. But they are seen living on land too. Today, we are going to discuss whether saltwater crabs can live in freshwater or not.

Can saltwater crabs live in freshwater?

Saltwater crabs can certainly live in freshwater. But they need enough time to adapt to the new condition and environment of freshwater. The condition and environment of the freshwater have to be altered by adding sea salt and dechlorinating products and only then saltwater crabs can live in it. 

Let’s look at different kinds of saltwater crabs and find out if they can live in freshwater.

Hermit crabs:

The scientific name of hermit crabs is Paguroidea. Hermit crabs are known for possessing a hard exoskeleton on the frontal side of their body. But they possess a soft tail on the remaining half of their body. They are also unable to produce their own shell.

Hermit crabs like to reside in the salty water of the ocean. There are approximately eight hundred species of crabs available. Out of these eight hundred, only the Clibanarius Fonticola is famous for being a freshwater crab.

The saltwater hermit crabs can certainly adapt to the condition of freshwater. Basically, saltwater hermit crabs require both saltwater and freshwater for their survival.

Blue crabs:

The other names of blue crabs are Chesapeake blue crabs and Atlantic blue crabs. These crabs are famous for having five pairs of legs. Blue crabs are generally small in size.

Blue crabs find brackish water best as their habitat. Brackish water is a mixture of freshwater and saltwater. So saltwater blue crabs can certainly live in freshwater. The female blue crabs sometimes need saltwater to lay eggs after the mating season.

As saltwater is important for their survival, it is wise to add a portion of saltwater to their freshwater habitat. The temperature of their freshwater habitat needs to be somewhere between seventy to eighty degrees Fahrenheit (F).

Shore crabs:

Shore crabs are one of the most famous species of crabs. They are found mainly on the shoreline most of the time as a herd.

Shore crabs are used to living in the salty water of the sea. But they can adapt to freshwater too. Saltwater shore crabs can certainly live in freshwater. You can make a habitat for shore crabs inside a fish tank containing freshwater.

The temperature of the tank needs to be maintained at seventy to seventy-five degrees Fahrenheit (F). You will also need to put sand at the bottom of the tank so that the shore crabs can adapt to the new environment easily.

Can crabs live in non-salt water?

Crabs are known for their adaptability. Most species of crabs are known for living in saltwater. But they can survive in non-salt water too. In fact, some species of crabs like blue crabs need the non-salt water portion for their survival. 

Many crabs can survive in brackish water which is a mixture of saltwater and freshwater.

Crabs are used to living in saltwater. But they can survive in the freshwater of fish tanks or in a freshwater pond. They need time to adapt to the environment of non-salt water. But once they settle in a non-salt water environment, it is very easy to take care of them.

Some species of crabs occasionally need saltwater for laying eggs. Saltwater is important for crabs to survive. But they can survive without it too. In fact, there are one hundred and three species of freshwater crabs available in the animal world.

How long can saltwater crabs live in freshwater?

Saltwater crabs are seen living in the salty water of the ocean. They need saltwater for mating and molting purposes. A saltwater crab will take time when it comes to adapting to a freshwater environment. You can take a saltwater crab from the shore and try to keep it in the fish tank. 

The saltwater crab will find it difficult at first to live in freshwater. But gradually, it will get used to the environment of freshwater.

Saltwater crabs surviving in freshwater depends on the kind of care it is getting. If the temperature of the freshwater is in the range of seventy to eighty degrees Fahrenheit (F), then saltwater crabs can reach their full lifespan in freshwater

One important thing to remember here is that freshwater needs to be chlorine-free.

What happens if you put a saltwater crab in freshwater?

There are several things that can happen if you put a saltwater crab in freshwater. Let’s discuss them in detail.

Can cause its demise:

There are some saltwater crabs who will struggle to adapt to the environment of freshwater. If a pure saltwater crab is put into pure freshwater, the environment of freshwater might cause the saltwater crab’s slow demise.

That is why it is needed to add some salt to the freshwater to make it tolerable for them. From living in saltwater to living in freshwater is a huge leap for saltwater crabs and most of them fail to adapt to this drastic change.

Can cause discomfort:

Some of the saltwater crabs will find it difficult at first to adapt to the environment of freshwater. But eventually, they get used to it. At first, you will notice the saltwater crabs trying rigorously to get out of the freshwater.

But as time passes, you will see the saltwater crabs adapting to the environment and condition of freshwater.

Longing for saltwater:

Saltwater crabs need saltwater when they need to mate and molt. That is why you will see them longing for saltwater when mating and molting season comes after being placed in freshwater.

Can cause health problems:

Chlorine is toxic to saltwater crabs. Saltwater crabs drink the water they live in. If your freshwater environment has chlorine in it, it will cause health problems for saltwater crabs.

How do you keep saltwater crabs alive in freshwater?

Keeping saltwater crabs alive in freshwater might seem like a difficult job. But it is an easy thing to do if you follow the steps properly. Let’s talk about some of the measures and steps that could be taken to keep saltwater crabs alive in freshwater.

By placing them in a tank:

You can start by placing the saltwater crabs in a fish tank. The water level of the fish tank needs to be under three feet. Too much water might drown the saltwater crabs.

By adding sand:

You will then have to add layers of sand at the bottom to give the saltwater crabs the feel of the shore. Saltwater crabs keep moving between the ocean and shoreline. The sand layers will make their adaptation easy.

By adding sea salt:

Saltwater crabs are used to living in the salty water of the ocean all their life. They drink the saltwater, bathe in it. They even need it for mating and molting. That is why the freshwater environment needs to be made suitable for their survival.

You can buy sea salt components from fish and aquarium supply stores. You will need to follow the instructions given on the sea salt product packaging to ensure the correct ratio of salt and water in your freshwater environment. 

It is better to put one ounce of salt for each quart of water.

By purifying the water:

Saltwater crabs can not survive in water that has chlorine in it. You have to use chlorine-free water in your fish tank for the saltwater crabs to survive. You can use dechlorinating components in the fish tank just to be sure.

Can you put sea salt in freshwater for hermit crabs?

You can put sea salt in freshwater for hermit crabs. But before putting sea salt, the freshwater itself has to be purified. Hermit crabs can not survive in plain tap water. The tap water contains chlorine which is harmful to them. 

The tap water has to be purified by using an aquarium water conditioner that will help to get rid of chlorine.

After the water has been made chlorine-free, mix the store-bought sea salt with it. You will need to use one ounce of sea salt for one quart of water. The sea salt will take time to dissolve in the freshwater.

After the freshwater mixture has reached room temperature, pour it into the fish tank. You can even buy readymade freshwater mixture from a fish and aquarium supply store if you want to avoid the hassle of making it yourself.

Final Thoughts

Saltwater crabs possess the ability to live in freshwater. But adequate time is needed for this adaptation to happen. The condition and environment of freshwater require changes in order to be tolerable to saltwater crabs. Adding sea salt and making the freshwater chlorine-free help the process.