Last Updated on: 4th October 2023, 02:25 pm
Betta fish are among the most popular pet fish because they look beautiful.
Many fish owners like to keep marine hermit crabs in an aquarium, as they often eat algae and reduce the need to clean the tank. Alas, betta fish and hermit crabs should never live together.
Bettas are freshwater fish, while hermit crabs are native to the ocean. Creating a shared living environment where fish and hermit crabs will feel comfortable and flourish is difficult.
Hermit crabs and betta fish have disparate dietary needs. Betta fish don’t sustain themselves entirely on flakes. Bettas are carnivorous and need protein, while hermit crabs need more calcium.
Betta fish are aggressive and territorial, which has earned them the name “Siamese fighting fish.” Hermit crabs are more relaxed but retaliate with their pinchers if threatened or attacked.
If you wish to keep betta fish, don’t rely on hermit crabs to keep their tank clean. Find a less aggressive saltwater fish if you want live fish to keep marine hermit crabs company.
Bettas and hermit crabs are too different to co-exist peacefully.
What Are Betta Fish?
Betta fish (Betta splendens) are native to Thailand but also found in Australia, Latin America, the Caribbean, and Singapore. This unofficial name stems from the Betta’s territorial nature.
Many fish owners like Bettas due to their striking appearance. They can live up to 3 years (if they don’t kill each other), grow up to 3 inches long, and prefer a carnivorous diet over flakes.
Anybody looking to care for betta fish should only combine females, as males of this species are the most prone to aggression. Think carefully before pairing Betta fish with another aquatic animal.
Can You Put Hermit Crabs with Betta Fish?
A terrestrial hermit crab can’t live with any fish. Land-based hermit crabs can’t breathe underwater and will drown within an hour of being placed in a deep aquarium without a means of escape.
Marine hermit crabs are the opposite; they need to live in water, as they can’t breathe on dry land for a prolonged period. Aquatic hermit crabs also eat naturally occurring algae in a fish tank, so some fish owners use them as an organic clean-up crew.
If you plan to pair marine hermit crabs with betta fish, you must first understand the needs of each animal. Here are the optimum tank conditions for Betta fish and marine hermit crabs:
| Betta Fish | Hermit Crabs | |
| Water Temperature | 75 – 86 OF | 72 – 78OF |
| Water pH | Around 7.0 | 8.0 – 8.4 |
| Water Hardness | 5 – 20 DH | 8 – 16 DH |
Except for Clibanarius Fonticola, it’s rarely kept in captivity, it doesn’t have a nickname, hermit crabs are saltwater animals, and bettas are freshwater fish.
This means that the water pH between these two animals is incompatible. Betta fish can cope with a slightly higher acidity than the freshwaters they’re used to but are unlikely to flourish.
Keeping water at a temperature safe for hermit crabs is also at the lower end of what a betta will need to remain comfortable. Perhaps most importantly, they have wildly different temperaments.
Do Hermit Crabs Eat Betta Fish?
Hermit crabs won’t actively hunt and attack fish to eat.
In truth, hermit crabs want to be left alone. They may eat a dead betta that sinks to the tank’s floor but will practically never attack and kill such a tankmate without provocation.
Will Betta Fish Attack Hermit Crabs?
While hermit crabs don’t hunt and kill betta fish, their docility should not be mistaken for wholesale subservience. If a betta fish attacks, the hermit crab will defend itself. The large cheliped of a hermit crab can kill a small betta.
This is a concern, as betta fish will likely attack hermit crabs sooner or later. They earned the nickname “fighting fish” for a reason. If a betta considers a hermit crab in its way, it’ll attack.
This lack of fear is admirable, but it’ll cost a betta fish its life when paired with hermit crabs. They defend themselves from perceived threats and predators and will emerge victorious from most conflicts.
Can Hermit Crabs Eat Betta Fish Food?
Hermit crabs are opportunistic scavengers, so they’ll eat anything unmoving. As discussed, many people keep hermit crabs in a fish tank to eat algae. Hermit crabs will also happily eat fish flakes that sink to the bottom of a tank.
Betta fish can be fed flakes, although offering a brand of flakes or granules intended for bettas is recommended. These will be rich in protein. Bettas also like to eat live or frozen shrimp or bloodworms.
Hermit crabs are omnivorous, so they can also eat these foods. Hermit crabs rarely hunt live prey; their primary need is calcium. While hermit crabs also need protein, sustaining themselves on a betta-specific diet is unlikely to meet their nutritional needs.
Betta flakes also contain ethoxyquin. While the International Journal of Food Sciences lauds the antioxidant properties of this preservative, it’s harmful to hermit crabs if regularly ingested over a prolonged period.
Consider how a betta will react if it spots a hermit crab eating its food. We have discussed how territorial these fish are. Conflict will follow if a fish attacks a hermit crab for ‘stealing’ its meal.
Alternative Tankmates for Betta Fish
Betta fish can’t live in groups, as they’ll fight. Males are the likeliest to come into conflict, but even female betta fish will likely come to blows eventually. The territorial nature of these fish will win out.
Rather than hermit crabs, consider keeping nerite snails in a betta fish tank. Like hermit crabs, snails will eat algae and keep the tank clean. However, unlike hermit crabs, they will mostly be ignored by bettas. Conflict will not arise, and both animals will be safe.
Nerite snails can live in freshwater tanks alongside betta fish and will not hatch their eggs in such surroundings. They are readily available from pet stores specializing in fish, rarely costing more than $3 each, and you can keep several in a betta tank.
Think carefully if you are determined to keep other fish with your bettas. Avoid any fish with bright, colorful scales, as these will aggravate the bettas. Stick with freshwater fish that dwell at the bottom or middle of a tank, as bettas will stick to the top.
Alternatives to Betta Fish to Keep with Hermit Crabs
Hermit crabs don’t need to live with fish but can do so with species other than the Betta.
If you want to pair fish with hermit crabs, choose saltwater fish with a similarly gentle temperament, unlikely to cause conflicts. Some ideal fish to pair with hermit crabs include:
- Clownfish.
- Damselfish.
- Gobiidae (Gobies).
- Pajama Cardinalfish.
- Royal Gramma.
- Wrasses.
Many of these fish live alongside hermit crabs in the ocean and will be unconcerned by their presence in a tank. It could be argued that hermit crabs make better tankmates than fellow fish, as they’re less likely to come into conflict over food, territory, or resources.
Betta fish and hermit crabs are from two different worlds and would never interact in the wild. To this end, there’s nothing to gain by forcing them to share an aquarium.
While some types of fish can share a tank with hermit crabs, bettas aren’t among them.
