Purple pincher

Question
my hermit crabs used to be tannish red. They didn't have much food at the petstore. When i bought them and moved them to their cage they ate allot but stayed the same color. then my grandmother gave them pineapple and the same day they both got dark purple pinchers, the small one got a little redder and the large ones legs turned a tad purple but pretty much stayed the same. The day before that i gave them a little cheese but i think thats not what turned them that color. Is the sudden change from tan to purple good or bad? And if it is good does that mean they are purple pinchers?

Answer
Dear Jeziel,
thank you for your question.
Food can change a crab's colour, but only when the crab molts. I suspect that the fruit acid from the pineappled may have reacted with the exoskeleton of the crabs.
Colour is not a reliable indicator of a crab's species. The first thing you need to look at are the eyes. PPs (Coenobita clypeatus) and C. brevimanus have eyes that are round like this oo, all other species have eyes that look more like this 00. Here's a website that has good pictures of the most common species and shows how to tell them apart:
http://www.tonycoenobita.com/species_eng.htm

Here are some websites that have a lot more good info on crab care, diet, molting and anything else to keep them happy and healthy:
www.thecrabbagepatch.com
www.hermitcrabassociation.com
www.landhermitcrabs.com
www.epicurean-hermit.com
www.hermit-crabs.com
http://www.crabbytalk.com/
http://crabstreetjournal.com/xoops/

I hope I was of some help to you
Jennifer