ALBA	Algae-bacteria model
COD	Chemical oxygen demand
DW	Dry weight
HRABP	High-rate algae bacteria pond
HRT	Hydraulic retention time
RG	Raceway ground
RR	Raceway raised
S${}_{NH}$	Ammoniacal nitrogen concentration
S${}_{N{O}_2}$	Nitrite concentration
S${}_{N{O}_3}$	Nitrate concentration
S${}_{O_2}$	Dissolved oxygen concentration
TA	Total alkalinity
TAN	Total ammoniacal nitrogen
TSS	Total suspended solids
VSS	Volatile suspended solids
X${}_{ALG}$	Algal biomass concentration
X${}_{AOB}$	Ammonium-oxidizing bacteria concentration
X${}_H$	Heterotrophic bacteria concentration
X${}_{NOB}$	Nitrite-oxidizing bacteria concentration