Bacterial attachment to the disc surface under different nutritional conditions 4 h after inoculation. Comparison of the growth media mFUM4 (A), iHS (B) and SAL (C). green: DNA staining using YoPro-1 + Sytox. The disc surface is visualized in grey colour. The images show representative areas of one disc each. Scale bars: 15 μm (A/B) and 10 μm (C).