Aiptasia-Eating Filefish (Acreichthys Tomentosus)

Also Known As: Matted Leatherjacket, Bristletail Filefish

Compatibility and Behavior Have an Aiptasia problem? The Aiptasia-Eating Filefish is one of those rare fish that's both genuinely useful and genuinely interesting to keep. Its claim to fame in the hobby is an appetite for nuisance Aiptasia anemones, but it's also a personable fish in its own right. The body shows a mottled camo green-brown base with irregular blotches and a fuzzy texture that helps it disappear against the rockwork, and the pointed snout paired with small undulating fins gives it a slow, deliberate swimming style that's almost meditative to watch. Personality-wise this is a peaceful to mildly assertive species that fits well into mixed communities with other non-aggressive fish. It's considered reef safe with caution. Many individuals focus primarily on Aiptasia and other pest anemones, but be warned that some might move on to fleshy LPS, soft corals, or zoanthids once the pest population thins out. In the right setup, the Aiptasia-Eating Filefish becomes both a quiet problem-solver and a fascinating fish to watch as it methodically combs the rockwork for targets.

Aquarium Requirements A mature aquarium with ample live rock, caves, and crevices is ideal, since foraging is core to how it spends the day. A peaceful environment with gentle to moderate flow helps the fish settle in and encourages that natural slow-cruising, picking behavior. Even when added specifically for Aiptasia control, supplemental food is important, especially once the pest population starts to drop off. Offer frozen mysis shrimp, finely chopped seafood, and quality marine omnivore pellets to keep the fish well-fed and less likely to look for trouble elsewhere. Stable water quality, a secure lid (they can occasionally jump), and non-aggressive tankmates all play a role in long-term success. When introducing one to a coral-heavy reef, plan for a trial period and watch closely for any coral nipping, since individual behavior varies a lot from fish to fish.

Specifications
Approximate Size:  Sm: 1-2", Md: 2-3", Lg: 3-4"
Diet: Omnivore (known to eat Aiptasia anemones)
Origin: Indo-Pacific
Care Level: Easy
Reef Safe: With caution (effective Aiptasia predator but may nip some corals, especially LPS, softies, or zoas)
Temperament: Peaceful
Minimum Tank Size: 30 gallons
Special Considerations: Effective Aiptasia predator but behavior varies by individual; coral nipping is a real possibility once pest Aiptasia are reduced