AEFW (Acropora-eating flatworms) are 3-5 mm tan flatworms (Amakusaplana acroporae) that feed on Acropora tissue. Bite marks appear as small white spots; advanced infestations strip tissue + leave bare skeleton.
Practical use in aquariums
Detection: blow water across acro with a turkey baster after lights-out - flatworms will be dislodged and visible. Treatment: Bayer Advanced dip every 5 days for 4-5 cycles to break the egg-hatch cycle. Quarantine all new acro for 30+ days. Wrasses (sixline, leopard, melanurus) provide some long-term control.
How AEFW fits the bigger picture
Understanding AEFW matters because it's connected to broader husbandry decisions: disease prevention is cheaper than treatment - quarantine + dipping protocols paid back the first time you avoid a tank-wide outbreak.
Whatever specific topic brought you here, four fundamentals govern long-term aquarium success: water quality, parameter stability, biological filtration, and species-appropriate husbandry. Skip any one and the others struggle to compensate.
Water quality: ammonia + nitrite at zero, nitrate under 30 ppm freshwater + 10 ppm reef. Test weekly with API or Salifert kits. Use our water parameter checker to score your readings against your tank type.
Parameter stability: stable wrong parameters beat fluctuating ideal parameters. Most fish tolerate a wide pH range if it's stable. Sudden swings of 0.4+ pH or 5+°F kill fish faster than chronic suboptimal values. Use temperature controllers (Inkbird) + automated dosing for consistency.
Biological filtration: the bacterial colony on your filter media + rock + substrate is the engine. Never replace all media at once. Use our filter turnover calculator to size correctly.
Why does my fish keep dying? 5 leading causes: uncycled tank, wrong species pairings, no quarantine, undersized tank, neglected water-change schedule. See full diagnosis.