What do you mean by cleaning behavior? Is it a kind of self cleaning or grooming (cleaning directed to itself) or alo cleaning (cleaning behavior towards con-specific or to the members of other species)? Or did you mean cleaning inanimate objects? In the first case, there are some works dealing with this subject:
- Little, E. E. and Finger, S. E. (1990), Swimming behavior as an indicator of sublethal toxicity in fish. Environmental Toxicology and Chemistry, 9: 13–19. doi: 10.1002/etc.5620090103
-Xinwei Lin, Hélène Volkoff, Yuwaraj Narnaware, Nicholas J Bernier, Pierre Peyon, Richard E Peter (2000) Brain regulation of feeding behavior and food intake in fish. Comparative Biochemistry and Physiology Part A: Molecular & Integrative Physiology, Volume 126, Issue 4, 1 August 2000, Pages 415–434
Thank you for the help. Corydoras is a kind of catfish and they eat algae, food pellet, microorganisms on the gravel, plants, or even glass-walls of the tank. Cleaning behaviour of the members of other species is common in some fish such as Labroids; however I'm not aware of such studies on the catfish.