Yelloweye filefish
Pervagor alternans
The Yelloweye filefish exhibits a distinctive bright yellow body with a pronounced, elongated dorsal fin and a prominent, rounded snout.
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About the Yelloweye filefish
A Western Pacific filefish with a bright yellow ring around the eye and an orange tail, it tops out around 6 inches and spends its time cruising coral and rocky reefs. It will pick at inverts and corals, so it is better in fish-only setups. When stressed it can even make a low grinding sound by rubbing its teeth together.
Also known as
Quick Facts
Size
16 cm
Temperament
Semi-aggressive
Difficulty
Intermediate
Min Tank Size
106 gallons
Lifespan
4-8 years
Origin
Western Pacific (east Australia, Lord Howe Island, New Caledonia, Marshall Islands, Tonga)
Diet
Omnivore - meaty foods plus algae; may nip invertebrates
Water Parameters
23.3-26.7°C
8.1-8.4
Need a heater for this species?
This species needs 23.3-26.7°C in a 106 gallon tank. Use our heater calculator to find the right wattage.
Calculate heater sizeCare Notes
- Give a Yelloweye filefish at least a 106-gallon marine tank with solid rock structure and some open swimming room; they naturally cruise coral and rocky reefs.
- Keep temperature at 23.3-26.7 C and pH at 8.1-8.4, and focus on stability rather than constant tweaking.
- Feed an omnivore mix: varied meaty marine foods plus algae-based fare; this species takes both.
- Plan a fish-only setup, because this filefish will pick at corals and invertebrates.
- Choose sturdy, confident tankmates; its semi-aggressive nature can bother small or timid fish.
- Expect a maximum size around 16 cm (about 6 inches) and a lifespan of roughly 4-8 years, so plan stocking and commitment accordingly.
- If you hear a low grinding sound, that is a stress signal from teeth rubbing; check for harassment or unstable parameters and make sure it has cover to duck into.
Compatibility
Good Tankmates
- Robust, non-aggressive tangs/surgeonfish (Zebrasoma, Ctenochaetus) that cruise open water
- Peaceful to moderately assertive fairy and flasher wrasses that are fast and alert
- Clownfish species that are not overly territorial (paired Amphiprion in a large tank)
- Dwarf or larger angelfish in fish-only systems with similar temperament
- Hawkfish that mostly perch and ignore tankmates
- Rabbitfish/foxface as calm, algae-grazing companions
Avoid
- Corals and ornamental invertebrates such as shrimp, snails, clams, and feather dusters (likely to be nipped)
- Triggerfish and very boisterous large wrasses that harass or outcompete calmer fish
- Puffers and boxfish that are nippy and may spar over similar foods
- Very small, timid nano fish that can be picked on or outcompeted
The Yelloweye filefish (Pervagor alternans) is a Western Pacific species recognized by a bright yellow ring around the eye and an orange tail. It reaches about 16 cm (around 6 inches), spends its days cruising coral and rocky reefs, and is best suited to fish-only marine aquariums. Expect intermediate care and a lifespan of roughly 4-8 years.
Origin and natural habitat
Native to the Western Pacific, this filefish is recorded from eastern Australia, Lord Howe Island, New Caledonia, the Marshall Islands, and Tonga. In the wild it patrols coral and rocky reef zones, picking at a mix of small invertebrates and algae as it moves through crevices and across hard substrates.
Aquarium setup and water conditions
House a single Yelloweye filefish in at least 106 US gallons. This is a roaming fish that appreciates open swimming space together with rockwork for cover and visual breaks. It is not a reef-safe choice and belongs in a fish-only or fish-only-with-live-rock system.
Keep stable marine conditions: temperature 23.3-26.7 C and pH 8.1-8.4. Larger volumes help buffer swings. Provide varied rockwork and caves so the fish can retreat if startled.
This species will pick at invertebrates and corals. Avoid housing it with ornamental shrimp, snails, crabs, or corals you care about.
Diet and feeding
An omnivore, the Yelloweye filefish takes meaty foods along with algae. Offer a varied menu to match that mix and to keep it occupied so it is less likely to sample tankmates.
- Meaty items: frozen mysis, enriched brine shrimp, finely chopped shrimp, clam, or other marine seafood
- Prepared foods: quality marine omnivore pellets or flakes it will accept
- Plant matter: sheets of marine algae (nori) or foods with marine algae content
Feed a variety over the week rather than one staple. Observing steady interest in both meaty foods and algae-based offerings helps keep nipping to a minimum.
Behavior and tankmates
Yelloweye filefish are semi-aggressive. They cruise the tank methodically and may investigate tankmates, especially slower or smaller ones, with exploratory nips. Choose robust, similarly sized fishes for a fish-only community and provide enough space and rockwork so residents can avoid each other.
A stressed Yelloweye filefish can make a low grinding sound by rubbing its teeth together. If you hear it, reduce stressors: dim the lights, give the fish space, and let it settle.
Common problems and how to reduce them
- Coral and invert losses: This species is not reef safe. Keep it in fish-only systems to avoid damage to corals and ornamental invertebrates.
- Persistent nipping: Underfeeding or a monotonous diet can make picking worse. Provide regular, varied feedings that include both meaty foods and algae.
- Territorial scuffles: Semi-aggressive behavior is amplified in tight quarters. Use the full recommended tank size and create line-of-sight breaks with rockwork.
- Stress after introduction: Give ample hiding places and maintain stable water parameters (23.3-26.7 C, pH 8.1-8.4) to help the fish settle.
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