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How To Keep Fiddler Crabs Alive? 

fiddler crabs
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If you are regularly involved in surf fishing, you should know that fiddler crabs make excellent bait. This is because you are more likely to catch fish with fiddler crabs as bait than conventional bait such as oysters or shrimp. But to use fiddler crabs as bait, it is essential to keep them alive. 

You will be surprised to know that keeping fiddler crabs alive is not that difficult. All you need to do is provide them with the right food and environment. You also need to do consistent monitoring and have adequate knowledge about them. 

To acquaint you with all the details and procedures, I have provided all the information about how to keep fiddler crabs alive in this article. I have also included a few additional details. I would recommend reading the whole article to enable you to properly cater to the crabs. 

What To Do To Keep Fiddler Crabs Alive? 

Fiddler crabs are low-maintenance and do not need much to stay alive. Some have been known to stay alive for almost 3 years with the proper care. In general, they can stay alive for weeks at a maximum. Yet, for their survival, you must ensure that they are in an environment quite similar to the habitat they have been used to throughout their lives.


For the storage of the fiddler crabs, you can store them in an aquarium. You can also use a cooler or a plastic container if you do have one. Their containment must have brackish water inside it to allow them to crawl inside it. This is important if you want to keep them for a long time. 

Crabs are quite social, so you can store them in large numbers. Yet, you need to ensure they have ample space to move around in their enclosure. In most cases, a container that holds approximately 20 gallons is ideal. Also, do not forget to securely keep the container’s lid shut, so your fiddler crabs do not run away. 

In addition, you need to make sure to include a sandy area inside the container or aquarium. This is because the crabs also need to escape from the water and crawl over something that resembles land.

You can combine coarse sand with very coarse sand for a better combination. It’s best to keep the sand on one side and the water on the other. Keep the sand level at least 20 cm. as crabs like a burrow. This way, the overall area will hold together. If you do not want the sand and water to blend, you can leave a layer of pebbles at the tank’s bottom. 

The most important thing is to ensure that the water has the right amount of salt. This is extremely significant because crabs are accustomed to seawater. The water should not be cold in any way. A suitable temperature range is 75-80 °F.


Molding is the process where the crabs shed their shells. They do so by squeezing and pushing all their appendages repeatedly. Sometimes, the fiddler crabs can go through the process of molding if you store them as bait for a long time.

Molding is a good sign. It means that the crabs are growing. It also indicates the crab population is in good health. Moreover, the exoskeletons that the crabs shed also serve as good nutrients that the crabs can feed off. Make sure you leave them inside the container for their own consumption. 

In some cases, crabs can lose their limbs or legs during the molding process. This is not a cause for concern. It does not affect their survival. Within a matter of weeks, the crabs will regenerate and grow back. 

Additional concerns 

It will never be possible to keep all fiddler crabs alive. In that case, there are some things you need to be aware of so that you can do as much damage control as possible. 

  • You need to regularly change the water inside the containment. If you keep the same water for long periods, it can leak an extremely foul smell throughout. This smell comes from fungus or if the water salinity is not proper. Such things can kill the fiddler crabs. 
  • The male fiddler crabs are mostly quite aggressive because their environment is too cramped up. They become quite territorial and violent by trying to fight the other crabs present inside the enclosure. It might be best to keep the male ones in a separate container. Try transferring them to a bigger container.
  • Remove them from the enclosure when some fiddler crabs die, which is nothing to be surprised by. If not, it can contaminate the other crabs that are still alive. This contamination can make their survival difficult. 

If you are looking for additional guidelines, look at this videoOpens in a new tab. here. 

What Is The Feeding Process For Fiddler Crabs? 

When it comes to feeding the fiddler crabs, you will have to be a little more attentive in comparison. This is because, in the event of overfeeding, the tank will have an unpleasant ammonia-like smell. It will also make the water soggy. 

Fiddler crabs are known to be scavengers as they like to feed on organic material they find lying throughout the confinement. Examples of their food can be organic plant matter, small dead fish, or chunks of shrimp. Do not throw whole pieces of shrimp, mullet, or anything else.

These crabs also do not need to be fed daily. You can feed them every other day or every 2 or 3 weeks. The consistency of these meals is enough for their good health. This will also help you as you will have to clean their enclosure less often. 

When it comes to strict monitoring, you need to regularly check the carbonate hardness and the pH level of the water. The pH should be between 8.0 and 8.3. Additionally, any number between 150-350 ppm is a favorable amount for carbonate hardness. 

How To Make Brackish Water At Home For Fiddler Crabs? 

Brackish water is basically water that is saltier than freshwater but less salty than seawater. Salted water is crucial to creating an environment for your fiddler crabs identical to their natural habitat. For your convenience, you can also make it at home. 

 Step 1: 

Get some sea salt. You will also need water that has been dechlorinated. 

Step 2: 

Mix 50 g of the marine salt with the dechlorinated water. 

Step 3: 

Pour the new mixture into the side of the container where you want it to be beside the sandy area. Ensure that the water level is 2.5 cm deep. 

Please do not substitute the mentioned elements with anything else, such as seawater or freshwater aquarium salt. They will not help with the survival of your fiddler crabs. 


I hope this article has helped you clear up all the questions you had about how to keep fiddler crabs alive. They are quite easy to maintain once you get into a proper routine. Certain things should still be monitored regularly to ensure they do not hinder your fishing experience. 

Wishing you a lovely day ahead!

Zaldy G.

I love feeling the cool ocean spray every time I hit the beach with a rod and a bucket of bait. I love the thrill of feeling bites on my line whenever I hook a big one. And I especially love the pride that comes with cooking a fresh catch and sharing it with my friends and family. Thank you for stopping by. Let's go catch some fish!

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