Many hermit crab owners are unaware that oils can be harmful—or even deadly—to their crabs. Whether it’s food-based oils, essential oils, or household products, it’s important to know what’s safe and what to avoid.
Many people use essential oils in their homes, but these can be toxic to hermit crabs.
Strong scents can stress out crabs, affecting their breathing and behavior.
Some oils contain compounds that can kill crabs on contact.
Crabs rely on their sense of smell to find food, and strong artificial scents can disrupt their instincts.
Especially Dangerous Essential Oils:
Tea Tree Oil
Peppermint Oil
Eucalyptus Oil
Citrus Oils (Lemon, Orange, Lime, etc.)
Pine Oil
Cinnamon Oil
Clove Oil
Tip: If you use essential oils in a diffuser or cleaner, keep your crab’s enclosure far away from the area.
While some natural oils are safe in tiny amounts, large amounts of fat can be harmful.
Greasy or fried foods can coat a crab’s gills, making it harder for them to breathe.
Processed cooking oils can go rancid and attract bacteria in the tank.
Avoid feeding foods cooked in:
Canola Oil
Vegetable Oil
Corn Oil
Peanut Oil
Hydrogenated Oils (used in processed foods)
Tip: If offering a food that naturally contains oil (like nuts), make sure it’s raw and unprocessed.
Some natural oils are safe and even beneficial for hermit crabs when given in tiny amounts as part of their diet. These can help with shell health, digestion, and energy.
100% natural coconut oil is one of the best oils for hermit crabs.
It provides healthy fats that support energy levels.
Some crabs like to eat it directly or use it for shell conditioning.
Do NOT overuse coconut oil! Too much can cause tank contamination. Offer a tiny amount once a month at most.
Can be offered in small amounts as a natural fat source.
Helps keep exoskeletons healthy.
Avoid processed olive oils that contain additives!
High in Omega-3 fatty acids, which can benefit crabs.
Should only be given in tiny amounts mixed with food.
Overuse can lead to spoiled food and bacterial growth.
Never place essential oils, air fresheners, or scented candles near your crab tank.
If feeding natural oils, use only a pinhead-sized amount once in a while.
Always check ingredient labels—avoid preservatives, artificial flavors, and hydrogenated oils.
If you suspect oil contamination in the tank, clean the surface and replace any affected substrate immediately.