The Aiptasia-Eating Filefish (Acreichthys tomentosus) is a unique saltwater species valued for its ability to control nuisance Aiptasia anemones in reef aquariums. Growing up to about 3–4 inches, this filefish has a mottled, chameleon-like body that allows it to camouflage within live rock. While it is generally hardy and peaceful, it can sometimes nip at corals, polyps, or other invertebrates once Aiptasia are gone, so careful monitoring is required in reef setups. They thrive in tanks of 30 gallons or larger with plenty of live rock for grazing and hiding. Provide a diet of frozen mysis, brine shrimp, and prepared marine foods to ensure long-term health. Stable reef-like water conditions, moderate flow, and peaceful tankmates make for the best environment for this useful but quirky fish.
Care Aspect
Details
Scientific Name
Acreichthys tomentosus
Common Name
Aiptasia-Eating Filefish / Matted Filefish
Family
Monacanthidae
Origin
Indo-Pacific
Size
3–4 inches (7–10 cm)
Lifespan
3–5 years
Temperament
Generally peaceful, may nip corals/inverts
Minimum Tank Size
30 gallons (115 liters)
Water Temperature
72–78°F (22–26°C)
pH
8.1–8.4
Salinity
1.020–1.025 SG
Diet
Omnivore – eats Aiptasia, frozen mysis, brine, prepared foods
Tank Setup
Live rock for grazing/hiding, stable reef-like conditions
Reef Safety
With caution – may nip corals and polyps once Aiptasia is gone
Compatibility
Peaceful community fish; avoid aggressive tankmates