“…An alternative hypothesis is that algal carbon is being consumed not as deposited living algae, but rather as detritus formed from decomposition or excretion of the algae, and that could not be measured as chlorophyll. The organic matter ingested by L. pardalis and P. nigricans is within the broad ranges (5-70%) reported for other fish belonging to this trophic guild (Gneri & Angelescu, 1951;Bowen, 1979Bowen, , 1982Odum, 1973;Bowen et al, 1984;De Silva et al, 1984;Araujo-Lima & Hardy, 1987;Almeida et al, 1993;Sutton & Bowen, 1994;Yap, 1995;Resende et al, 1995;Catella, unpubl.). Crude protein contents were similar to the values reported for P. platensis and Tilapia mossambica (Peters) in South America (3·5-12%) (Bowen, 1981(Bowen, , 1984.…”