In the wild Land Hermit Crabs are scavengers, so they will eat basically anything. The best food for your hermit crab is specially formulated food sold by retailers. The Land Hermit crab food contains animal and vegetable substances, and an addition of vitamins and minerals. Although, there is this formulated food for them, I would not give them just this food. The reason being that is they need a variety of different foods just like we do to keep a balanced diet. Hermit crabs eat sporadically, similar to Goldfish. Sometimes they will eat a lot and at other times very little.
They should be fed each day and you should remove any uneaten food from the previous day. If they have eaten all the food from the previous feeding, try to give them a little more this way you can soon be able to discern the proper amount of food. Here is a small list of some foods that they can be given from the 4 basic food groups for a Hermit crab:
Following this guide will ensure that your hermit crab lives a long and healthy life with a well balanced diet.
Hermit Crab Care is a website where you can learn everything you need to know to keep happy and healthy hermit crabs.
This article is from the Hermit Crab Care website http://www.hermit-crab-care.com/articles/feeding-land-hermit-crab/6.htm