Table 1. Experimental reactor characteristics.

Parameter	daily-fed reactor	hourly-fed reactor
reactor volume	2 L	3 L
vol. of media fed per day	150 ml	150 ml
hydraulic retention time	13.3 days	20 days
date of inoculation	March 2008	January 2002
pH	7.3	7.4
CH4 % in headspace	54%	56%