fights for the right to mate with them. In the wild they have very set molting schedules of once per year,
but in North America, captive crabs seem to breed between February and August with the most reports
occurring in June and July. Eggs are ready to hatch roughly a month after mating occurs, and you may or
may not see signs of the zoea in the water dish or eggs spread around the enclosure as the mother and
other hermit crabs will eat them.
It is almost impossible to rear young hermit crabs. Their larvae are ocean plankton for weeks after
hatching, and it takes specialized equipment and a lot of time and effort to get any to survive in
captivity. Only a few people have ever managed this successfully, and several have tried. We hope that
more owners will try in the future as we learn more about the process. Someday we may be able to
breed hermit crabs readily in captivity, and hopefully there will be no more need for wild harvesting.
Maintenance
Assuming you provide your crabbies with a proper environment, they require relatively low
maintenance. You should check the temperature and humidity every day and make adjustments as
necessary. For instance, if the humidity is too high, you can prop open the glass cover a bit, or remove a
small amount of saran wrap from the mesh. If the humidity is too low, you can prop the cover less, add
more saran wrap, or check to make sure the substrate is staying moist enough. You should also remove
any fresh food from the previous day to prevent spoilage, and make sure the water dishes are full and
clean. Keeping the water clean is of utmost importance, as crabs can be very sensitive to water quality.
Every week, you need to completely clean out the water and food bowls.. If you have large water basins
that are filtered and aerated, they still need to be completely cleaned once a month unless they are
cycled. You can also spot-clean poo from the tank, although if your sand or coconut fiber is kept
properly moist, beneficial microbes will naturally recycle the poo.
In the past it was often recommended to completely change your substrate after a set period, but many
crabbers now choose to wait until the crabitat actually needs such a deep cleaning rather than follow a
set schedule. Many have been using the same substrate for years with no problems! If you feel the
need, substrate can be fully removed and replaced with fresh, and some old substrate can be retained
to mix into the new to retain a familiar scent and for the good things that might be in the substrate. Try
to work around the times when your crabs are molting so that there isn't any risk to them. It’s never a
bad idea every few months to wash items in the tank in hot water. Cholla, driftwood, and cork can be
microwaved for a couple of minutes while wet to kill any bacteria or mold.
Regular bathing used to be recommended, but it is no longer. Hermit crabs auto-regulate the salinity of
their shell water (osmoregulation), and stock up before molting. Bathing disrupts their shell water and
can stress them, plus you should never dig up buried crabs. Provided the proper fresh and salt water
bowls, they will clean themselves. The only time baths should be considered is when you are
introducing two unfamiliar hermit crabs, adding a new crab into an established tank, or when one crab is
getting picked on. Making the new or picked on crab smell neutral will often prevent or stop fights.