Head and Lateral Line Erosion (HLLE)

From Fish
A chevron tang with HLLE on its left side only, right side was clear of symptoms
Yellow tangs frequently develop atypical symptoms of HLLE

Head and lateral line erosion (HLLE) is an environmental disease of aquarium fish, often confused with Hole in the head parasitic infections[1].

HLLD is a chronic dermatopathy affecting a number of fish that presents as depigmented skin along the lateral line system of the trunk and head[2]. The sensory lateral line system runs along the sides of the body and head receives stimuli from the aquatic environment and mediates adaptive responses through the CNS.


A number of contributing causes include dietary deficiencies, poor water quality, lack of sunlight, exposure to copper and stray tank voltage.


Treatments require assessment of all aspects of aquarium husbandry.

Suggested pharmaceutical remedies include Regranex (Becaplermin).


  1. Noga, Ed. (2000) Fish Disease: Diagnosis and Treatment. Iowa State University Press. Ames, Iowa. pp:245-246
  2. Corrales J, Ullal A, Noga EJ. (2009) Lateral line depigmentation (LLD) in channel catfish, Ictalurus punctatus (Rafinesque). J Fish Dis 32(8):705-12