Item | SS Reduction (%) | VSS Reduction (%) | Growth rate of earthworm weight (%) | Increase rate of earthworm density (%) | Increase rate of earthworm biomass (%) | Filter’s maximum sludge capability (g/L) |
Filter height | 0.127 | 0.178 | 0.852 | 0.765 | 0.975** | 0.921* |
Filling diameter | −0.464 | −0.513 | 0.746 | −0.538 | 0.835 | 0.986** |
Influent concentration | −0.508 | −0.550 | −0.655 | −0.546 | −0.807 | −0.957* |