What Do Hermit Crabs Eat? A Complete Feeding Guide

Hermit crabs are amazing little creatures — but most people don’t realize how much their health depends on what they eat. The good news? Feeding them doesn’t have to be complicated. This guide will show you exactly hermit crabs need, what to avoid, and the easiest way to keep them happy and thriving.

Why Food Matters So Much

In the wild, hermit crabs are natural scavengers. They roam beaches and forests, eating a little bit of everything — leaves, fruit, fish, shells, and even soil. That variety isn't just fun for them. It's essential.

When hermit crabs don't get the right nutrients, they get stressed. They stop growing. Their molts (the process where they shed their exoskeleton to grow) can fail — and a failed molt can be fatal.

The right diet changes everything.

Protein Is the Most Important Thing You Can Feed Your Hermit Crab

If there's one thing to remember from this guide, it's this: hermit crabs need protein, and they need a lot of it.

Protein does the heavy lifting in a hermit crab's body. It powers their daily energy, helps them grow, repairs their muscles, and — most importantly — supports healthy molting. Without enough protein, your crab simply can't thrive.

Think of protein as the engine. Everything else supports it.

Hermit crabs thrive on a wide variety of protein sources — and the more you rotate, the better. Great options include:

Meat proteins — Chicken Breast, Chicken Hearts, and beef (found in our Sunday Pot Roast Complete Meal)
Fish and seafood — Salmon, Cod Bites, Salmon Rolls
Ocean proteins — Krill, Mysis Shrimp, Plankton, Bloodworms
Whole proteins — Whole Quail Egg Yolk
Insects — Mealworms, Black Soldier Fly Larvae, Jiminy Crickets Complete Meal, and earthworms

Want to offer a wide range of proteins without buying each one separately? The Gimme The Meats! 12 Proteins and Land & Sea Protein Set are great ways to rotate through a full variety.

The Other Things Hermit Crabs Need

Protein is the priority — but a truly healthy hermit crab needs more than that. Here's what else matters and why:

Calcium — Hermit crabs use calcium to rebuild their exoskeleton after every molt. Without enough of it, molts can go wrong.

Fruits and vegetables — These deliver vitamins, antioxidants, and natural sugars that fuel daily activity.

Healthy fats — Fats support normal growth, healthy molting, and overall health.

Minerals — Trace minerals support nerve function, hydration, and overall body health.

Harvestables — Natural botanicals and foraged ingredients add enrichment and trace nutrients your crab would find in the wild.

No single food covers everything — which is exactly why variety and rotation are so important.

What to Never Feed Your Hermit Crab

Not all food is good food. Avoid anything with:

Preservatives — Avoid foods with preservatives whenever possible. Hermit crabs do best with simple, whole ingredients.
Copper sulfate — A common ingredient in commercial pet store pellets. It's harmful and should be avoided entirely.
Artificial colors or flavors — If it's not something you'd find in nature, skip it.

A good rule of thumb: if you can't recognize every ingredient on the label, don't feed it to your crab.

How to Feed Your Hermit Crab: The Buffet Method

Here's where it gets fun. The best way to feed hermit crabs is something we call the buffet method — and it's exactly how it sounds.

You set out two dishes every evening. One holds the core staples that never change. The other is the buffet — a rotating spread of small scoops placed side by side, each one offering something different. Your crab walks over, explores the buffet, and eats exactly what their body needs that day.

That's it. No guessing. No complicated schedules. Just variety and instinct doing their thing.

Dish 1: The Core (Always Out, Never Changes)

The core is your foundation. These three things stay available 24/7:

Green Sand — A natural mineral supplement that supports hydration, nerve health, and overall wellness. Think of it as a daily vitamin.
Worm Castings — A nutrient-dense soil amendment packed with beneficial microbes and trace nutrients that supports gut health and overall vitality.
A calcium source — Always keep one available. Great choices include Crushed Crab and Lobster Shell, Blue Crab Shell, Oyster Shell Flour, Cuttlebone, Eggshells, and more.

Dish 2: The Buffet (Rotates Daily or Every Few Days)

Add a small scoop of each category, placed side by side in one dish:

Two Complete Meals — Rotate between flavors to cover a wide range of nutrients
A protein — Salmon, Krill, Chicken Breast, Bloodworms, Whole Quail Egg Yolk, and more — pick one and rotate regularly
A fruit or veggie — Spinach Pieces, Goji Berries, Super Sweet Corn, Zucchini, and more
A calcium source — Crushed Crab and Lobster Shell, Oyster Shell Flour, Cuttlebone, Eggshells, and more
A healthy fat — Shredded Coconut, Black Chia Seeds, Norwegian Virgin Salmon Oil, and more
A harvestable — Foraging Mix, Raspberry Leaf, Bladderwrack Seaweed, and more
An extra — Something rotating like Flower Confetti, Cotton Candy, or a seasonal treat

Set it out in the evening and let your crab do the rest.

Make It Easy With Complete Meals

Each Complete Meal is a carefully balanced blend of proteins, fruits, vegetables, and minerals — all in one jar. No mixing. No measuring. Just one scoop placed right in the buffet dish. That's it.

Try the Blue Octopus Complete Meal for a protein-rich ocean-inspired blend, or the Color Me Purple Complete Mealfor a vibrant mix packed with antioxidant-rich ingredients. Rotate between flavors to keep your crab's diet exciting and varied.

Ready to Build the Perfect Buffet?

Start with your core dish — Green Sand, Worm Castings, and a calcium source — set it in the tank and leave it. Then build your buffet dish each evening with a couple of Complete Meals, a protein, a fruit or veggie, a healthy fat, a harvestable, and something extra. Refresh the buffet daily whenever possible, or every couple of days if the food remains fresh, and you’re done.

The Best Sellers Bundle is the easiest way to get started. It's packed with our most-loved foods so you can build your first buffet with confidence.

Your hermit crab is going to love it. 🦀

Have questions about what to feed your hermit crab? Browse our full collection at Hermit Grub where you’ll find thoughtfully selected foods made specifically for hermit crabs.