8 Biofilter Aquaponic System for Nutrients …
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Nitrification (aerobic)
Oreochromis niloticus
and fertilizer from oil
palm plantation
produces ammonia
Ammonia nitrogen
NH 4 -N
Nitrite nitrogen
NO 2 -N
Nitrate nitrogen
NO 3 -N
Hydrolysis and
ammonificatio
Nitrosomonas
+ oxygen
Nitrobacteria +
oxygen
Fig. 8.2 Nitrification process
to N 2 gas through heterotrophic biological denitrification as shown in the following
unbalanced equation (US EPA 1993):
NO
−
3 + Organic matter → N 2 + CO 2 + OH
−
+ H 2 O
(8.1)