HCA: Hermit Crab Association

I think lots of foods that we dont expect to have calcium in them do, ive put together a list of some foods that are great for the crabs that have calcium.. I bet some on here you would not of expected to have calcium in them!

Sardines
salmon
Broccoli
Turnip greens
Kale
Egg
Spinach
Cuttle bone
shrimp exoskeletons
shrimp with exoskeletons
Crushed oyster shell
mineral supplements
Beet greens
Bok choy
Cabbage
Carrots
Swiss Chard
Collards
Cucumber
corn
Dandelion greens
Eggplant
Mushrooms
oat straw
soybeans
Squash
Sweet potato
Turnip greens
watercress
Water chestnuts
Yam

Many plants with a lot of calcium also have a high content of oxalic acids, which binds calcium in the body. Parsley for example, with 1.7g oxalic acids per 100g.
Calcium:phosphorus ratio is also important for the same reason, although most vegetables have a good ratio. Fruits often contain a lot more phosphorus than calcium.

Kale and squashes for example are great because their are both low on oxalic acids and have a Ca:P ratio of 2.4:1 / 1.9-1.5/1.
The IguanaDen website explains it all very well and has lists of veggies/fruits with their Ca:P ratio and oxalic acid contents:
http://www.iguanaden.org/diet/

Iguanas are not decapods.. the digestive system is quite different. Im sure that makes a difference too.

Great list, thanks so much for sharing it. I have kept reptiles for years but this is our first real go at hermit crabs. Still working on giving them a perfect diet so this helps a lot. I was curious about the Ca:P ratio since it was mentioned so I did a light search but didn't find much. But I did find this:

http://hermitcrabfoodtrials.blogspot.co ... atios.html

Not sure how accurate it is (like I said was just a light search) but seemed to make sense. Any thoughts? I really kind of agree with statement that if you give enough variety the crabs will choose the items they need. It seems they self regulate a lot of other things, why not their nutrition intake as well? Definitely interesting, gonna have to do some more digging on this one.

You will find that no matter what you offer they eat certain things.. they know what part of the molting cycle they are in and what they need at that time.. Its best to offer a varied diet so that they can get what they want. I do not mix my foods so that they can pick and choose what they need at the time.. If you keep the basics in your tank at all times.. Worm castings for protein, Crushed oyster shell and a cuttle bone for calcium, and mineral supplement, as well as offer fresh coconut at least once every two weeks at the least, offer fresh raw nuts for the nut oils, shrimp exos, vegetables for the vitamins and the plant proteins, along with fresh fruit and grains you will have healthy crabs with healthy molts.. of course they also need the fresh de chlorinated and mineral grade sea salt de chlorinated water. All of that is important to get them through the molt cycles. They know what they need when.. you will find one thing that they wont touch offered many times weeks later is the favorite thing in the tank.

Re Ca:P ratio: It doesn't make a difference because the absorption of calcium does not depend on the digestive system. It's a simple chemical process, not depending on the kind of animal that eats the plant.

Crabs won't be harmed by the calcium oxalates that are produced when oxalic acids absorp calcium. They just pass their digestive system (in mammals and reptiles, they can form kidney stones). The calcium is still gone, though, and can't be used by their digestive system.

Oxalic acids can be destroyed by boiling or at least reduced.

i gave my hermies crushed and boiled egg shell and put it in their substrate and i also mixed with their food. Is this ok?

you dont have to mix it with the food you can offer it as a separate dish they will eat it if they need calcium. Egg shell is a good source and is fine to offer..

I also heard that mixing in the egg shells with the sand is good. Does anyone have opinions or facts about that. Because I would like to powder up my eggshells in with my sand.
But would that work???

BROCCOLI that's what I've been dying to try, I need to buy some organic broccoli for them. Which reminds me, they'll be needing some carrots tonight.

Hey!! I have a question can my crabs eat oats. I have the container that says 100 % rolled oats. NO other ingrediant, and no preservatives.
It's the one with the quaker oats guy on it.

Rolled oats are on the safe food list. I haven't tried them. Let us know how the crabs like them.

i looked on the safe food list but it didn't say rolled oat, so I wasn't sure. But thanx for the help
i'm glad someone replied

it is on the list. oops. Sorry u were right, i was actually looking under oats or oatmeanl :/ thanx!!!!