Adding biocides to water is one strategy to control macrofouling organisms. A natural biocide that helps to prevent/control macrofouling of Limnoperna fortunei (Dunker, 1857) on human installations is one way to minimize environmental impacts of different control strategies. Laboratory tests were carried out to evaluate effects of three commercial tannis preparations (ECOTEC®-UA, ECOTEC®-L and ECOTEC®-MC) on the survival of two life-history stages (larvae and adults) of L. fortunei. In addition tests were performed on two non-target species, a crustacean Daphnia magna and a plant Lactuca sativa, to evaluate effects of these tannins on the aquatic environment. The larvae of L. fortunei were more vulnerable to the concentrations of the three tannins than adults. The two nontarget species were not affected at concentrations that were effective for larvae. These results suggest that these products could be used as biocides to control macrofouling caused by L. fortunei.Fil: Pereyra, Patricio Javier. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Bulus Rossini, Gustavo Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Departamento de Química. Centro de Investigaciones del Medio Ambiente; ArgentinaFil: Darrigran, Gustavo Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo; Argentin
