Two species of macroalgae (Undaria pinnatifida and Gracilaria vermiculophylla) collected from the Russian Far-East were evaluated in laboratory experiments to determine their potential as biofilters. For this purpose, their nutrient uptake potential and their physiological response to wastewater effluents from a maricultural rearing system (mussels’ culture) were measured.

8 g (fresh weight) of macroalgae were placed by replicate in 2 L containers with a continuous flow of wastewater. Water samples were taken to measure the ammonium- and phosphate concentrations and calculate the nutrient uptake rate. During the experiments, the temperature was maintained at 15°C, the irradiance was fixed at 130 µmol photons m-2 s-1, and the aeration was supplied continuously.

The results obtained indicated that both species of macroalgae can reduce the nutrient concentrations in the water (up to 70-90% of ammonium and 35-82% of phosphates). Besides, any negative effect on the growth and physiological conditions of both macroalgae species were found.

The study suggests that both species have great potential as a biofilter. Furthermore, the macroalgae species tested have great economic potential, being another good reason to use in IMTA.

For more details please visit: Skriptsova and Miroshnikova (2011). Laboratory experiment to determine the potential of two macroalgae from the Russian Far-East as biofilters for integrated multi-trophic aquaculture (IMTA). Bioresource Technology 102, 3149-3154.