The Pitho Crab, Pitho mirabilis, is a small and hardy algae-eating crab that has become a favourite among Canadian reef keepers. Peaceful, reef-safe, and low maintenance, it plays an important role in keeping aquariums clean and balanced. Its constant grazing helps prevent nuisance algae from taking over, making it one of the most effective natural cleaners available for marine tanks in Canada.
Behaviour and Compatibility
The Pitho Crab is a gentle and reef-safe scavenger that spends most of its time exploring live rock in search of algae and organic matter. It does not bother corals or other invertebrates, making it a great choice for mixed reef tanks. Providing plenty of live rock and hiding spots encourages natural foraging behaviour and helps the crab feel secure. It is also nocturnal by nature, becoming more active at night.
What Types of Algae Pitho Crabs Eat
Pitho Crabs are known for their ability to eat several types of problem algae that many aquarists struggle to control. They readily consume bubble algae, hair algae, and film algae, which commonly appear on rocks and aquarium glass. They will also graze on small amounts of red slime algae and macroalgae such as Ulva or Caulerpa. Their natural diet extends to leftover fish food and detritus, helping maintain excellent water quality and reducing nutrient buildup.
Feeding and Supplementation
In most tanks, the Pitho Crab will find enough natural food to sustain itself. However, if algae levels are low, supplemental feeding is recommended. Offer marine algae sheets, nori, or sinking pellets to ensure proper nutrition. A small amount of frozen food once or twice a week can also support their overall health and activity.
Tank Requirements
This small crab grows to about one inch, making it ideal for nano tanks as well as larger reef aquariums. It thrives in stable marine conditions with moderate water flow and clean, well-oxygenated water. Consistent salinity and temperature are key to long-term success.
Care Summary
Care Level: Easy
Diet: Omnivore (algae, detritus, prepared foods)
Maximum Size: 1 inch
Temperament: Peaceful
Family: Majidae
Why Choose the Pitho Crab
For reef aquarists in Canada looking to manage algae naturally, the Pitho Crab is an excellent choice. It is affordable, hardy, and highly effective against bubble algae and other unwanted growths. By adding one or more to your cleanup crew, you can keep your reef tank looking clean, healthy, and vibrant with minimal effort.
You can order the Pitho Crab directly from Aquarium Depot, Canada’s trusted source for saltwater fish and invertebrates.