HCA: Hermit Crab Association

Hi everyone!
I first became interested in hermit crabs when my little sitster came back from a field trip with two hermit crabs in a kritter carrier. Now they are in a nice big place with proper temp, humidity, and assortment of food. We also have seven now.
Well science fair is coming up and I just inherited a GIANT aquarium like probably more than 5 ft across from my uncle. I would love a reason to set it up, if I don't have one, such school i doubt I will be able to set it up because of my parents.

I'm wondering if there are any projects that anyone can think of using hermit crabs and manipulating their environment without hurting them or putting them in danger.

I was thinking maybe seeing how diet affects color and activity (Or just color) any input on that?
And ideas would be awesome, thanks!

-Sofia

Or another idea is to see whether having salt water it the aquarium makes them any more active than those without, and since I only have purple pincher's who don't necessarily need salt water (It's recommended but I don't think it's life or death) they should be okay.

Hope to hear some input

I think I'm going to have to scratch that diet one because I don't have enough time for them to molt.

Or maybe I could get many different shell types and see how different temperatures affect shell type

I think those are all good ideas, but depending on what kind of time frame you have...

You could lay out different shells and keep track of how often your crab goes to each one.

You could use foods and just see which ones they prefer....say fresh vs. frozen vs. commercial

You could use the tank as two sided with some with light and some without and collect data on their activity levels.

Hope you have a wonderful time getting ready for the fair and good luck talking your parents into letting you keep the tank!