A wide variety of aerobic and anaerobic bacteria are able
to express urease (urea amidohydrolase) which catalyzes the
hydrolysis of urea to ammonia and carbon dioxide (reviewed
by Mobley and Hausinger, 1989). Bearing in mind that urea is
excreted and hydrolyzed to ammonia within aquaculture systems,
this dissolved N-fraction would have to be accounted for when
assessing/calculating biofilter capacity based on ammonia loading
(Wheaton et al., 1994)