Two, no-choice feeding experiments were used to test how initial concentration and age affected clearance rates by the green-lipped mussel (Perna canaliculus) of macroalgal-derived particulate material (MDPM) originating from common large brown algae with relatively high (fucoids: Cystophora retroflexa, Cystophora torulosa) and low (laminarians: Macrocystis pyrifera, Undaria pinnatifida-) phlorotannin concentrations from southern New Zealand. Mussels removed fresh MDPM originating from each species but removal rates of MDPM were higher for the low phlorotannin species than for the higher phlorotannin species. Clearance rates of MDPM ranging from fresh, 14 and 28-day old material decreased with age in C. retroflexa and M. pyrifera, but not for MDPM from C. torulosa and U. pinnatifida-. Initial MDPM concentrations present to mussels ranged from 0.017 to 0.126 g L-1 and removal rates were positively correlated with increasing concentrations from fresh MDPM from C. torulosa, M. pyrifera, and U. pinnatifida-. We did not observe a relationship with increasing concentration and removal rates of MDPM from C. retroflexa. In addition, we report carbon to nitrogen mass ratios (C:N) and nutritional profiles of mature blade material collected from C. retroflexa, C. torulosa, M. pyrifera, and U. pinnatifida- to consider the implications of selective clearance of MDPM on nutritional profiles from macroalgal detritus. We found that the two laminarian species had lower median C:N ratios than the fucoids, which was largely reflective of significant differences in total carbohydrate and crude protein content. Interspecific differences in phlorotannin concentrations and nutritional quality of organic matter produced by large brown algae have important consequences for the availability of organic matter originating from macroalgal communities and ecosystem function of coastal food webs.