The growth of Azolla in a solution of 5% pig waste and in a maturation pond effluent, were, carried out
in PVC reactors (detention time, tr=10 d), with 18.3l
capacity, within confining PVC frames (A=0.11 m2), inside a Fitoclima 750 E culture chamber. Controlled
conditions were: 25±0.5 ◦C, during 14 h d light (31Wm−2) and 18±0.5 ◦C during 10/h night period; humidity
was between 70 and 75%.The methodology for growth rate, density and productivity evaluation has been described earlier (Costa et al., 1994, 1996).