Fig. 3.

Representative FISH-CLSM digital images illustrating changes in the population composition and architecture of the biomass during the start-up period (Phase I) in R1 (a–d) and R2 (e–h). Anammox populations (AMX; Amx820+Bfu613 oligonucleotides labeled with the fluorescent probe Cy3) are displayed with red color allocation and aerobic ammonium-oxidizing bacteria (AOB; AOB-mix, FLUOS) in cyan. The border of biomass aggregates is highlighted with a dashed white line in order to facilitate the interpretation of the images (scale bars: 20 μm). (For interpretation of the references to color in this figure legend, the reader is referred to the web version of this article.)