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Essentials of hermit crab care
At the Jersey Shore...
I was at the Jersey shore a few years ago when my kids and I caught sight of a large cage filled with dozens of crabs with colorful painted shells. We stopped and looked with fascination and before long I was buying a hermit crab. The sales lady's instructions were "Give it fresh water daily and hermit crab food, that's all". It seemed simple enough. To my disappointment (especially my kids!), Hermie didn't last much over a month. This past summer, we were back at the Jersey Shore and once again, my kids wanted a hermit crab. We took Leo (named after the ninja turtle, Leonardo) home, but this time I decided to find out all I needed to know about hermit crab care!
This terrarium is great because it also has incandescent light bulbs on the lid which may help in keeping the right temperature.
Leo gets a new home - a glass tank! - and choosing a tank substrate...
Hermit crabs come from tropical regions. They are clean, disease-free, and I learned that once the essential requirements are provided, hermit crabs can be a simple and fun pet to care for. The first thing I needed to do was create a proper hermit crab habitat or "crabitat" - as some people like to call it. So, this means Leo gets a new home! I bought a 10 gallon glass tank and was happy to get rid of the wire cage that he came in.
The next thing I needed to know about hermit crab care was how to set up Leo's crabitat in his new tank. Hermit crabs are diggers by nature. They may need to dig underground to de-stress, molt, or just because they want to. So, I needed to choose a substrate that would allow Leo to do this and it should be deep enough for him to bury himself completely underground.
There are 2 types of glass tanks: aquariums and terrariums. Either of these are good, just keep in mind that terrariums are made of a thinner glass, so make sure it can safely hold the proper amount of substrate or sand.
SAND, COCONUT FIBER OR BOTH...
The safest substrates for hermit crabs are sand and coconut fiber. Many pet stores sell hermit crab sand (which also comes in different colors!) or you could simply buy some play sand. Coconut fiber substrate such as Eco Earth also works well. It comes in two forms: loose in a bag or compressed in the shape of a brick. Compressed coconut fiber will have to be soaked in salt water and the excess water squeezed before adding it to the tank.
I chose to use a combination of the two for the best of both worlds and also because coconut fiber helps retain moisture. It's important that I always keep Leo's crabitat substrate moist enough for him to dig, burrow, and form tunnels. It has to be damp enough that it holds its shape when you squeeze, but not so wet that it drips or bacteria may start to grow at the bottom of his tank. So, I'm using a combination that many hermit crab owners prefer which is made of a mixture of 5:1. This means that for every 5 parts of equal sand, 1 equal part of coconut fiber is used.
This also comes in many colors.
I chose this substrate and mixed it with sand, but you can have an all coco-fiber substrate too.
Just recently purchased this item myself.
Hermit Crab Supplies...
Next, some hermit crab supplies to complete Leo's crabitat paradise.
DISHES & WATER TREATMENT:
Hermit crabs always need a bowl of fresh water and a bowl of ocean salt water in their crabitat. So, I have two different water dishes deep enough for Leo to fully submerge itself. I've added a small natural sponge in each dish to help him safely come out and avoid drowning. It's also important to buy a water de-chlorinator because tap water has chlorine and other chemicals that are harmful to hermit crabs. I bought Zoo Med's Hermit Crab Drinking Water Conditioner from Amazon, but any aquarium water conditioner will do the trick.
Buying a salt conditioner is also important because table salt is not safe to use. It contains iodine which can be harmful to hermit crabs. Instant Ocean is a popular brand that I use. As for Leo's food dish, I chose to use a seashell over a dish just to add to the tropical atmosphere.
EXTRA SHELLS, FOOD & OTHER ACCESSORIES:
Hermit crabs wear shells to protect their soft abdomens so as they grow they will need bigger and bigger shells. I've provided several shells for Leo that have openings slightly larger than its current one. It's recommended that you have 2-3 extra shells of different sizes for each crab in your crabitat.
Quality food and treats should be available in the tank at all times. There are many commercial foods sold that come in powder or large, hard pellets. I will usually crush the pellets for Leo. The best thing to do is to supplement your hermit crab's food with fresh or dried fruits, veggies and meats. It's also recommended that you add some calcium powder or crushed cuttlebone to their diet.
Hermit crabs love to hide, climb and explore, so I've added some fun accessories in the tank. I've added a small half log and a coconut hut that Leo can crawl into and hide. Cholla wood, driftwood, cork bark, fake plants and netting are great additions too. I'm also exploring ways to add a second level so Leo has more room to explore!
Leo loves this crab shack!
There are other varieties of food you can try.
Get both in one at a good price.
Hermit Crab Supplies... - humidity & temperature gauges
It's very important that I maintain the proper temperature and humidity in Leo's crabitat so that he remains active and comfy in a moist and tropical environment. I keep a humidity gauge in the tank to make sure that the crabitat remains between 70 and 80% relative humidity. This is critical because hermit crabs breathe using modified gills that need to remain moist at all times or they will slowly suffocate and die.To help keep the proper humidity, I mist Leo's crabitat daily and keep the substrate moist.
Heating Leo's crabitat is also important so I also keep a thermometer gauge in the tank. The ideal temperature is between 72 and 84 degrees Fahrenheit. I try to aim for 78-80. The best way to provide heat is to get a 15 watt reptile heat lamp or an under tank heater (UTH). If you use a UTH, be sure to use it on the side or the back of the tank so that it's more effective.
Great choice for critical monitoring and it has a digital display too!
This is ideal for a 10-20 gallon tank.
Leo gets a crabby friend! - and more to learn about hermit crab care...
I found out that despite their name, hermit crabs are very sociable. So, a few weeks later I got Leo a crabby friend named Goji (short for Gojira, and according to my son, Japanese for Godzilla!). In the wild, hermit crabs live in large colonies, so it's recommended that you get no less than 2 hermit crabs because lonely crabs become very inactive and have a shortened life span.
This is not all you'll need to to know about hermit crab care, but it's a great essential start. Properly caring for hermit crabs like Leo and Goji takes time and effort, but it's also fun!
Fun Fact Poll
The shell on this crab is similar to Leo's. This pic was posted at www.gadgetscience.com by Heath Nichols.
Did you know that hermit crabs are nocturnal, so they are most active in the evening and at night?
5 Crabby Fun Facts
1. Hermit crabs can grow from the size of a marble to the size of a baseball!
2. Hermit crabs can make a chirping noise and scientists have yet to concretely explain how and why they do it!
3. There are more than 600 species of hermit crabs in the world!
4. Some hermit crabs have lived as long as 15 years in captivity!
5. Hermit crabs drink by dipping their claws in water and depositing the water into their gills and mouth!
This pic was posted on flickr by Arthur Chapman.