Productivity and Elemental/Chlorophyll Composition of Collard Greens in an Aquaponic System at Different Combinations of Media and Black Soldier Fly (Hermetia illucens) Larvae Frass Supplementations

Table 2

Mean (±SE) water quality characteristics over 10 weeks in aquaponic systems receiving black soldier fly (Hermetia illucens) larvae frass or none that was sampled from the sump.

Water quality	No frass	Frass	-values
Dissolved oxygen (mg/L)	7.26 ± 0.24	7.14 ± 0.46	0.882
pH	7.36 ± 0.11	7.32 ± 0.18	0.743
Hardness (mg/L CaCO3)	78.32 ± 0.44	83.21 ± 0.57	0.580
Ammonia-N (mg/L)	0.10 ± 0.05	0.15 ± 0.09	0.649
Nitrite-N (mg/L)	0.05 ± 0.00	0.05 ± 0.00	0.945
Nitrate-N (mg/L)	15.32 ± 0.78	18.72 ± 0.93	0.582
Temperature (°C)	19.15 ± 2.56	20.38 ± 2.86	0.825