How to Breed Hermit Crabs

Prepare a salt-water tank. Hermit crabs breathe through modified gills so they need moistened air. Use a hygrometer to ensure that the relative humidity of the tank remains between 75 percent and 90 percent. Hermit crabs are tropical animals. Use a thermometer to ensure that the temperature of the tank and water remains between 72 and 80 degrees Fahrenheit.

Install a wavemaker. Wavemakers are machines that mimic the irregular currents of the ocean by turning small, submersible pumps on and off at different locations in the aquarium. You can buy wavemakers at your local pet store.

Install moonlight bulbs around your tank. These low-heat bulbs give off a bluish light that imitates moonlight and stimulates breeding behavior. Do not use black lights as a replacement because black light emits a lot of UVA rays, which don't simulate moonlight.

Ascertain the sex of your hermit crabs. A female hermit crab has small genital openings that can be found on the back pair of walking legs. These openings, or gonopores, are located on the first segment, which is the one closest to her body. They can be very hard to see, especially because hermit crabs won't always come out of their shells far enough for you to see their hind walking legs. If your crab doesn't have gonopores, then it's a male.

Put the breeding pair in your tank by itself. Do not allow other hermit crabs in the same tank. Keep the tank clean and make sure your hermit crabs have fresh water and plenty of calcium-rich foods. You can buy calcium-enriched hermit crab food at the pet store. You can also buy cuttlebone powder, to add calcium to other foods you provide. Hermit crabs are omnivores and eat a variety of foods including plants, decaying wood, dead crustaceans, fruits, vegetables and meats.

Watch your hermit crabs. You may see them performing a mating "dance" over a two- or three-week period. Keep brine shrimp on hand, to feed the larvae that hatch from the eggs, if your hermit crabs successfully breed.