{HEAD ~ A method} and apparatus for monitoring {TAIL ~ a liquid} undergoing anaerobic fermentation in a vessel is disclosed 
for monitoring
{ HEAD ~ A method } and apparatus for monitoring { TAIL ~ a liquid } undergoing anaerobic fermentation in a vessel is disclosed
HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH