Crab cages are available in different styles. The specs of the cage will depend on how many crabs you want to take care of. A single hermit crab is about the size of a baseball. But you need to make the crab cage dimensions bigger than that.
Several kinds of cages exist. Three types are popular: crab pots, star/pyramid traps and ring nets. The ring nets are the cheapest. They consist of a couple of rings, the top bigger than the one on the bottom. A mesh net connects it. It is set at the ocean flooring. When you pull the trap, the upper ring is pulled off. This will capture the crabs. The problem with ring nets is they break easily.
Star and Pyramid Traps
These are composed of metal wires. They function like the ring net in many ways. The difference is the string connected to the ends of four triangular sides. A pyramid shape is formed when the sides are drawn up. The problem with this type is that one of the sides caught underneath may land up.
Regardless of the crab cage dimensions used, these models are the most efficient. They have a couple of internal areas. The bottom part has at least two tunnel-shaped entryways. This permits the crab to go in but not leave.
In the center is the bait box. The bait is covered in wire so the crab cannot get to it. Once the creature enters, it is caught. The only option is to swim, but this will lead only to the upper portion.
Crab Pot Features
Many of these cages are built from PVC coated wire. Others have extra room for the bait. Some models have openings so small crabs can get out. This is useful if you want to catch crabs of a specific size.
How Crabs are Trapped
Other variants exist, but they function the same way. The bait is installed at the bottom in a bag. It is fastened to the bottom. A string is hooked to the cage. The cage is thrown in the water. The cage sides will go down.
The ocean sand hides the sides. The bait draws the attention of the crabs. When the cage is pulled up, the cage sides go up, trapping the creatures. You can then haul them up. The number of crabs you can capture depends on the crab cage dimensions.