Biofilms grown for 64.5 h in iHS Medium. FISH staining of a fixed biofilm; the biofilm base in the side views is directed towards the top view. C. rectus is shown schematically as dots (fluorescence maxima of the cells). (A) red: A. oris, green: non-hybridised cells, DNA staining (YoPro-1 + Sytox), blue: EPS. (B) red: C. rectus, green: non-hybridised cells, DNA staining (YoPro-1 + Sytox). The red dots appear yellowish due to the transparency of the green channel. Figures show a representative area of one disc. Scale bars: 20 μm.