Table 4. Change of water quality (DO, pH, temperature, EC, turbidity, TAN, NO₂-N, NO₃-N and PO₄-P) in HBFT-AP for 12 weeks

Diet	Week	DO (mg/L)	pH	Temperature (°C)	EC (μs/cm)	Turbidity (NTU)	TAN (mg/L)	NO2-N (mg/L)	NO3-N (mg/L)	PO4-P (mg/L)
Mash	initial	8.94	8.42	25.8	159.8	0.4	0.13	0.082	3.49	1.07
	1	8.62 ± 0.40	8.21 ± 0.12	24.0 ± 2.3	167.4 ± 6.9	2.53 ± 0.77	1.14 ± 0.86	0.185 ± 0.091	2.89 ± 0.22	0.80 ± 0.36
	2	8.33 ± 0.18	7.27 ± 0.42	25.3 ± 1.0	230.9 ± 16.8	1.20 ± 0.57	0.18 ± 0.06	0.118 ± 0.047	14.36 ± 2.24	4.47 ± 0.34
	3	8.17 ± 0.24	6.29 ± 0.28	25.2 ± 1.0	286.9 ± 11.6	0.95 ± 0.17	0.36 ± 0.80	0.042 ± 0.025	20.50 ± 0.81	4.78 ± 0.11
	4	8.16 ± 0.28	6.18 ± 0.16	25.3 ± 1.1	316.8 ± 8.4	0.82 ± 0.24	0.60 ± 0.41	0.031 ± 0.014	24.70 ± 0.54	4.98 ± 0.07
	5	8.58 ± 0.28	5.95 ± 0.03	24.8 ± 0.6	320.7 ± 1.1	1.73 ± 0.21	1.18 ± 0.21	0.021 ± 0.008	25.37 ± 0.35	4.87 ± 0.10
	6	8.44 ± 0.44	5.81 ± 0.11	25.0 ± 1.3	335.6 ± 2.3	1.80 ± 0.17	1.22 ± 0.05	0.018 ± 0.002	26.77 ± 0.83	4.46 ± 0.72
EP	7	8.24 ± 0.08	5.53 ± 0.04	24.8 ± 0.7	337.4 ± 5.0	0.90 ± 0.14	2.11 ± 0.03	0.008 ± 0.000	24.35 ± 0.07	4.24 ± 0.21
	8	8.32 ± 0.08	5.66 ± 0.11	23.8 ± 0.0	343.5 ± 13.3	1.20 ± 0.00	2.44 ± 0.21	0.018 ± 0.001	24.50 ± 0.99	4.29 ± 1.21
	9	8.04 ± 0.12	5.57 ± 0.20	26.0 ± 0.1	352.8 ± 0.21	0.45 ± 0.21	2.19 ± 0.18	0.012 ± 0.008	26.90 ± 0.14	4.29 ± 0.78
	10	8.41 ± 0.06	5.64 ± 0.14	24.0 ± 0.3	383.5 ± 12.9	0.95 ± 0.10	3.11 ± 0.06	0.012 ± 0.004	28.45 ± 0.24	4.84 ± 0.28
	11	8.06 ± 0.19	5.53 ± 0.07	25.6 ± 1.1	422.2 ± 8.4	1.06 ± 0.37	3.14 ± 0.04	0.014 ± 0.001	31.82 ± 1.39	4.93 ± 0.19
	12	8.12 ± 0.16	5.57 ± 0.04	25.6 ± 1.0	440.1 ± 6.8	0.48 ± 0.10	4.15 ± 0.02	0.014 ± 0.002	33.98 ± 1.39	4.94 ± 0.30

Values represent the means ± SD of the values for 7 days.
EC, electrical conductivity; TAN, total ammonia nitrogen; HBFT-AP, hybrid biofloc technology-aquaponics; Mash, commercial powdered feed; EP, extruded pellet.