60, 100 m and control treatments. However, presence of micro-screen or mesh size did not significantly affect the decrease in CODDISS observed (p = 0.783). CODPART and CODDISS trends affected CODTOTAL(p = 0.032), and at day 42, average CODTOTAL was 52 mgO2L−1for the control group, and 30, 25 and 30 mg O2L−1for the100 m, 60 m and 20 m groups, respectively