More than 94 species of fiddler crabs make up the Uca genus of the Ocypodidae family. Lots of animal stores offer Uca minax, red-jointed fiddler crabs, for home fish tanks and hobbyists to raise and enjoy. Fiddler crabs are relatively small, typically measuring 1 to 2 inches– so they do not need substantial aquariums.
The Fiddler Crab in Water Tank
In the wild, fiddler crabs are native to marshes, swamps and mudflats with brackish water and sand or mud surface. Your captive fiddlers need both land and water areas in their fish tank. When developing a fish tank, you wish to ensure the ratio of land and water is 50/50. In order to be able to develop sufficient housing area, you’ll require a fish tank of no less than 10 gallons for as much as four crabs.
The Fiddler Crab Walks on Land
There are different ways to establish the acreage area inside the fish tank. You can use plexiglass or a fish tank divider to different land and water. Or, you can use substrate to develop a sloping surface, the substrate sloping into the water so the crab can get onto land. Use coarse sand, such as aquarium sand, play sand or swimming pool filter sand for the land. The fiddler crab is a burrower, so you don’t want to use gravel throughout the acreage; he will sift through the sand to find bits of food.
How Much Water Do Crabs Need?
A fiddler crab needs a water area, however you wish to see the salinity, as the fiddler crab isn’t 100 percent freshwater. If you preserve the water as freshwater, the crab will not make it through long; however if you guarantee minor salinity, making brackish water, the fiddler crab can live up to three years. You want to preserve the water specific gravity between 1.005 to 1.015 by adding marine salt to the water– find out the appropriate amount for your species and the water volume. When setting up the water area, it’s a great idea to include small pebbles or gravel to the bottom of the tank and to produce a slope so the crab can easily climb up in and out of the water.
Lighting and Temperature
As soon as the water and acreage of the fish tank are established, you wish to ensure the temperature is accurate. Use a digital thermometer with a probe to ensure the temperature is between 75 and 82 degrees Fahrenheit. If the aquarium requires additional heat, use a reptile-specific heat bulb. You can position the fixture above the land area so the fiddler crab can climb from the water and bask to warm up.
What and How Do Crabs Eat in a Fish Tank
The fiddler crab is a scavenger; he will sift through the sand and between gravel for food. In the wild, he will eat algae and any organic matter he finds. In captivity, you can feed a fiddler crab a variety of industrial foods, including algae wagers, sinking pellets, specialized crab food, dried bloodworms, shrimp and krill. You can offer blanched zucchini, blanched peas and raw or boiled fish.