English: Supplementary Movie 2 Star Diamond Mine at -640 meter. Using the endoscope the recording starts at the end of the >1 meter long metal tube casing and shows the end of the borehole casing into a small rock chamber covered with filamentous biofilm. For reference the borehole diameter is 4.5 cm in diameter. The white out of focus covering of the tube itself is biofilm. The resolution is less than the previous video due to a different less powerful camera and the relatively weak lighting offered by the built in LEDs. Resolution improves as the camera reaches the massive biofilm growth in the chamber due the reflection of the LED lights on the white biofilm. The tube casing is covered in white cotton like biofilm moving in the current of the outgoing flow. At t+57 seconds the endoscope has entered the rock chamber. In the chamber the biofilm gets longer and clearly moves in the current. From T+64 seconds it is clearly visible that the biofilm is attached to the rock face. The resolution was 640 x 480 at 25 fps and recorded as an AVI file. Per journal instruction the file was converted to a MOV format (H264) and deinterlaced using WinX video converter without any other changes. For scale, the diameter of the borehole is 1.5 cm.