Composite FISH micrographs of the "Ca. Fermentibacter spp." in the Randers anaerobic digester sludge."Ca. Fermentibacter spp." cells appear red (Hyd24-12_659, Cy3), other bacterial cells appear blue (EUBmix probe set, Cy5) and archaeal cells appear green (ARCH915, FLUOS). - Source:1Fermentation
Based on annotation of representative genomes, derived from full-scale mesophilic anaerobic digesters, it appears that members have a primarily fermentative metabolism. They appear to be strict anaerobes with no TCA cycle and possibly utilise elemental sulfur as an electron acceptor. Cells are small rods typically distributed throughout the biomass 1.
Hyd24-12658; Hyd24-12468 1
 Kirkegaard, Dueholm, McIlroy, Nierychlo, Karst, Albertsen, et al. (2016): Genomic insights into members of the candidate phylum Hyd24-12 common in mesophilic anaerobic digesters. ISME J 10(10): 2352-64. doi:10.1038/ismej.2016.43