Blue Damselfish

 Quick Care Facts

• Care Level: Easy   • Temperament: Aggressive   • Maximum Size: 3"
• Minimum Tank Size: 30 gallons   • Water Conditions: 72-80° F, dKH 8-12, pH 8.1-8.4, sg 1.020-1.025
• Diet: Omnivore   • Origin: Western Pacific
• Family: Pomacentridae   • Species: Damselfish   • Aquarium Type: Reef Compatible

Help Support AquariumDomain!      

• Your support keeps AquariumDomain advertisement free, lightning fast and fully optimized for both mobile and desktop browsing.

• Visit our Patreon page to learn about the exclusive benefits our Patrons receive!

Blue Damselfish are one the hardiest marine fish species and are often used by hobbyists to cycle newly setup aquariums. In the wild, Blue Damselfish are mainly found defending their small territories throughout the coral reefs of the Indo-Pacific. The Blue Damselfish has earned the nickname of Blue Devil in direct relation to the relentless aggression directed towards any fish that comes near their territory (especially their own kind). The Blue Damselfish is one of the most popular and best selling marine species in the world; as such, they are easy to find through local and online vendors and are very inexpensive to purchase.

Blue Damselfish prefer slightly more space than their small size may indicate and should be provided with an aquarium of at least 30 gallons (multiple specimens would require more space as well as many separate territories to alleviate aggression). Their environment should have a fine sand to crushed coral substrate and an adequate amount of territory and shelter provided by plenty of live rock. They do not have any special lighting needs, but higher lighting will surely make their vibrant blue coloration stand out. Standard, quality biological and mechanical filtration is sufficient as they are small and have a relatively low impact on a system.

They can be highly aggressive towards conspecific tank mates and will even harass much larger tank mates that stray to close to their territory; tank mates should be chosen carefully and would normally consist of Angelfish, Butterflyfish, small groupers, wrasse, Clownfish, pseudochromis, and several others; but when in doubt it's always a good idea to add the Blue Damselfish last.

Blue Damselfish are omnivorous and are not very picky with what they will accept. They should be provided with a well balanced and varied diet of live, frozen, freeze-dried, and vitamin enriched foods such as brine shrimp, finely chopped mysis shrimp, and other prepared foods such as Spirulina-based, carnivore and herbivore pellets and flakes.