Bioassay of antifoulant chlorine

Abstract

Laboratory bioassays were conducted using laboratory cultured, young settling stages as well as adults of major fouling species, with a view to determining suitable chlorine dosage and chlorination cycle to mitigate biofouling. Fairly high concentration of chlorine was required to cause death of the larvae. It was, however, possible to prevent settlement by desensitising the larvae with low levels of residual chlorine. To remove fouling by adults was very difficult. Residual chlorine as high as 15-20 ppm for a period of 60 hr would be necessary to remove settled biofouling.