Combined measurements of sea-ice core pigment concentrations, spectral ice algal and detrital absorption coefficients and hyperspectral transmitted under-ice irradiances were carried out in the 115–130° E sector off East Antarctica in September and October 2007 during the Sea Ice Physics and Ecosystems eXperiment (SIPEX). Ice thickness and snow thickness at the sampling sites varied from 0.32 to 1.30 m and 0.01 to 0.24 m, respectively. Total integrated chlorophyll a concentrations ranged from 0.05 mg m^–2 to 2.87 mg m^–2 and were not correlated to ice or snow thickness. High-performance liquid chromatography (HPLC) algal marker pigment analysis indicated that ice algal biomass was dominated by diatoms. Haptophytes were present at 30 out of 32 stations, while dinoflagellates and cryptophytes occurred in low concentrations at a few stations only. Spectral ice algal absorption coefficients showed typical maxima at 440 and 670 nm, while detrital absorption showed a characteristic exponential increase at shorter wavelengths. Detrital absorption coefficients at 440 nm (ad(440), range: 0.002–0.038 m^–1) exceeded ice algal absorption (aph(440), range: 0.003–0.558 m^–1) at 12 out of 32 sampling sites, indicating the importance of the detrital fraction to overall particulate absorption in the sea ice under investigation. Under-ice irradiance spectra showed distinct local minima at 440 and 670 nm indicating the potential to estimate ice algal biomass from light measurements taken from beneath sea ice. However, the application of different algorithms to determine ice algal biomass (integrated pigment concentration) from under-ice irradiance showed only weak relationships. We attribute these weak relationships to both the overall low ice algal biomass and relative high contribution of detrital matter in the sea ice under investigation. Our study provides the first combined information on East Antarctic pack-ice algal community pigment composition and particulate absorption, and their influence on the under-ice spectral light composition.