The dimensions of the experimental channel, as described in Materials & Methods: Overview of the experimental channel & equipment, allowed results to be correlated to a travel time of approximately 4.8 days.
Among the basic parameters, the temperature of the water is one of the most important characteristics of the aquatic medium and plays an important role in the control of the parameters monitored and, in the FGX3 experimental channel an average temperature of 23.5 ° C was maintained which is ideal for maintenance of aquatic life in the river corridor.
With respect to pH, the results in the range from 7.51 to 7.81, were in the optimal range required in Article 17, Item VII, CONAMA 357 for Class 4 rivers of pH 6.0 to pH 9.
The water collected from the Pinheiros River used to feed into the experimental channels, showed dissolved oxygen (DO) near 0 mg/l in almost every test period, rising to 1.00 mg/l only twice.
The requirement for OD of Article 17 of CONAMA Resolution 357, for rivers with Class 4 is the maintenance of 2.0 mg/l over the entire length of the river.
With the application of FGX3 on channel 3 an average of 5.00 mg/l of DO resulted not only in compliance with the legislation but reaching an increase of over 200 % above the regulatory requirement. Figure 4 illustrates the comparison of the effluent inlet 15 m (intermediate) and effluent output required by CONAMA. Further, throughout the test period, it was found that the OD was above the level recommended by law, as illustrated in Figure 11.