| Treatment |
NH4-Na |
NO2-Na |
NO3-Na |
PO4-Pa |
pH |
T Alka |
Chl aa |
SSa |
TSSa |
| 1.4 kg/m3 |
|
|
|
|
|
|
|
|
|
| Initial |
1.01 |
0.02 |
0.00 |
7.85 |
8.7 |
217.1 |
661.8 |
3 |
105.4 |
| Final |
0.02 |
0.03 |
94.91 |
23.58 |
7.5 |
84.4 |
1,694.0 |
57 |
667.8 |
| Pooled SE |
0.38 |
0.01 |
5.54 |
0.63 |
0.0 |
4.5 |
197.9 |
1 |
16.5 |
| Pr > F |
0.139 |
0.671 |
0.007 |
0.002 |
0.002 |
< 0.001 |
0.026 |
< 0.001 |
< 0.001 |
| 2.1 kg/m3 |
|
|
|
|
|
|
|
|
|
| Initial |
0.84 |
0.03 |
0.00 |
8.32 |
8.7 |
214.1 |
675.9 |
4 |
114.8 |
| Final |
0.02 |
0.02 |
112.60 |
28.35 |
7.3 |
76.8 |
1,471.5 |
75 |
760.0 |
| Pooled SE |
0.37 |
0.01 |
11.51 |
2.01 |
0.1 |
4.4 |
231.0 |
7 |
41.4 |
| Pr > F |
0.260 |
0.895 |
0.020 |
0.002 |
< 0.001 |
< 0.001 |
0.072 |
0.002 |
0.005 |
| 2.8 kg/m3 |
|
|
|
|
|
|
|
|
|
| Initial |
0.41 |
0.03 |
0.00 |
7.48 |
8.7 |
218.4 |
602.8 |
4 |
102.2 |
| Final |
0.02 |
0.03 |
130.88 |
32.67 |
7.3 |
81.6 |
1,048.2 |
68 |
753.3 |
| Pooled SE |
0.14 |
0.01 |
6.45 |
0.70 |
0.1 |
6.8 |
234.9 |
1 |
25.0 |
| Pr > F |
0.128 |
0.982 |
0.005 |
< 0.001 |
< 0.001 |
0.002 |
0.251 |
< 0.001 |
< 0.001 |
|
| a Total ammonia nitrogen (mg/L NH4-N), nitrite-nitrogen (mg/L NO2-N), nitrate-nitrogen (mg/L NO3-N), soluble reactive phosphorus (mg/L PO4-P), total alkalinity (mg/L as CaCO3 T Alk), chlorophyll a (mg/m3 Chl a), settleable solids (mL/L SS), and total suspended solids (mg/L TSS). |
| Table 2: Within treatment comparison of least squares mean (± SE) initial and final water quality variable concentrations for outdoor biofloc technology tanks stocked with large (217 g/fish) channel catfish at 1.4–2.8 kg/m3. |
