The Role of Activated Lignite Carbon in the Development of Head and Lateral Line Erosion in the Ocean Surgeon

Abstract

Head and lateral line erosion (HLLE) is an acute or chronic, often progressive problem affecting captive fishes. Its etiology is enigmatic. This study examined the relationship between the use of activated carbon as a filtrant and the development of HLLE lesions in ocean surgeons Acanthurus bahianus. Three identical, 454-L marine aquarium systems were established. Thirty-five ocean surgeons were distributed among the three aquarium systems. Activated lignite carbon was added to one system, and pelleted carbon was added to the second system. The fish in the third system were not exposed to any carbon. All 12 fish that were exposed to lignite carbon developed severe HLLE within 3 months. The 12 fish that were exposed to pelleted carbon did not develop gross symptoms, but microscopic lesions were discovered upon histological examination. The 11 control fish did not develop any visible or microscopic lesions. Based on these results, the use of activated lignite carbon in marine aquariums that house HLLE-susceptible species is discouraged.

Received February 4, 2011; accepted April 9, 2011

ACKNOWLEDGMENTS

This publication and research were funded by the Toledo Zoo Foundation and the Toledo Zoological Society. We thank the personnel at the Toledo Zoo aquarium for their assistance in managing the study aquariums. Editorial assistance was provided by Ron Fricke, Chris Hanley, Eric Klinger, and Peter Tolson.