Some Photos used or adapted under the 'Creative Commons Attribution 4.0 International license: https://creativecommons.org/licenses/by/2.0/legalcode
Algae simulation photos courtesy of https://www.flickr.com/photos/roland/6072275564/; https://www.flickr.com/photos/roland/6072279038/
Sluice Riffle photos courtesy of Daniel Beckwitt https://upload.wikimedia.org/wikipedia/commons/1/12/Sluice_Riffle.jpg
Digesters photos courtesy of Mike Steinhoff https://www.flickr.com/photos/-aismist/8211403515/; https://www.flickr.com/photos/-aismist/8211402241/
Anaerobic Biofilm photos courtesy of 'KoiQuestion' https://www.flickr.com/photos/koiquest10/7022155369/
Bacterial (E.Coli) photos courtesy of 'NIAID' https://www.flickr.com/photos/niaid/16578744517/;
Yellowstone photos courtesy of Timothy Pearce https://www.flickr.com/photos/timpearcelosgatos/5272531809/;