The investigation of water hyacinth production in this study
included three sets of experiments.Oneset of experiments included
a 9-tank system (Fig. 2) that was used to investigate the impact of
water hyacinth harvest frequency on water hyacinth growth rate.
The designed treatments (harvest frequency) were one harvest per
week, one harvest in 2 weeks, and one harvest in 4 weeks. The
9-tank system was divided into three subsets with each subset corresponding
to one treatment. Each subset had three water tanks
(replications) with height of 0.54m and radius of 0.27 m. The total
nitrogen (TN) concentration in the supply water of the system was
maintained at approximately 25 mg/L for the research period. The
produced water hyacinth was harvested by removing plants from
one-half of the water surface of the tank with the remaining half
being allowed to reproduce and grow. The study started on April
2007 and ended on October 2008.