Table 5 Hydroponic physico-chemical water parameters (means ± SD) in the fertiliser control tank (Control) and the experimental aquaculture process water tanks (extensive: AET-E; intensive: AET-I) with light parameters between planting tables of Humicacid Fiber-Substrate (HFS) and standard growth media substrate (Einheitserde, E) trial (light intensity, PPFD); different letters showing different groups (p < 0.05; p-I: significance value (p) between Control & EAU; p-II: between Control & IAU; p-III: between EAU and IAU).

8.6 ± 0.2^a

8.6 ± 0.2^a

8.6 ± 0.3^a

0.702

0.702

0.702

103.9 ± 1.5^a

104.0 ± 1.1^a

103.5 ± 2.6^a

0.887

0.887

0.887

24.6 ± 1.1^a

25.1 ± 1.2^a

25.0 ± 1.3^a

0.278

0.479

0.924

6.0 ± 0.1^a

5.9 ± 0.1^b

6.0 ± 0.2^a

0.025

1.000

0.002

2,011.8 ± 72.4^a

995.7 ± 89.4^c

1,708.2 ± 173.2^b

0.001

0.001

0.001

1.0 ± 0.0^a

0.5 ± 0.0^c

0.9 ± 0.1^b

0.001

0.001

0.001

185.4 ± 15.6^a

176.3 ± 9.3^a

181.3 ± 17.4^a

0.054

0.536

0.407

11.91 ± 9.19^a

0.43 ± 0.24^b

1.35 ± 0.96^ab

0.001

0.078

0.057

1.09 ± 2.28^a

0.05 ± 0.07^a

0.22 ± 0.23^a

0.095

0.095

0.095

116.47 ± 16.07^a

57.69 ± 9.08^b

144.00 ± 20.15^a

0.015

0.125

0.001

117.57 ± 14.99^a

57.72 ± 9.07^b

144.22 ± 20.05^a

0.015

0.125

0.001

128.29 ± 16.51^a

53.30 ± 18.74^b

145.35 ± 19.76^a

0.003

0.637

0.001

64.56 ± 17.01^a

17.25 ± 7.28^b

24.42 ± 15.73^b

0.001

0.003

0.805

320.41 ± 36.05^a

7.98 ± 2.09^b

18.23 ± 5.40^b

0.001

0.020

0.063

47.84 ± 5.57^a

21.86 ± 4.72^b

27.15 ± 8.39^b

0.001

0.011

0.255

96.16 ± 14.34^b

129.90 ± 28.18^b

232.34 ± 47.42^a

0.064

0.001

0.017

0.01 ± 0.01^b

0.02 ± 0.01^a

0.02 ± 0.01^a

0.013

0.040

1.000

68.14 ± 8.46^a

30.34 ± 3.51^b

37.91 ± 14.05^b

0.001

0.005

0.633

330.1 ± 265.5^a

323.7 ± 245.0^a

382.9 ± 263.6^a

0.695

0.695

0.695

462.0 ± 344.0^a

516.0 ± 390.1^a

510.9 ± 384.4^a

0.861

0.861

0.861

372.4 ± 243.1^a

354.7 ± 252.1^a

329.7 ± 236.1^a

0.893

0.893

0.893

585.0 ± 419.2^a

582.5 ± 405.5^a

551.1 ± 403.0^a

0.951

0.951

0.951