Use seaweeds on nutrient reduction in super-intensive vaname pond wastewater

Fisheries Research Center of the Fisheries, Earth and Maritime Research Organization, National Research and Innovation Agency (BRIN), 16911 Bogor, Indonesia

^* Corresponding author: mat.fahrur@brin.go.id

Abstract

This research was carried out at the Waste Water Treatment Plant (IPAL) in super intensive vaname shrimp cultivation. Wastewater discharged into the sea through wastewater treatment has high N and P contents. Grass is known to have effective absorption of N and P. Therefore, this study aims to determine the absorption capacity of the seaweed Gracillaria gigas, Gracillaria verrucosa, and Eucheuma spinosum on N and P in wastewater from super intensive pond wastewater treatment plants. The experiment utilized aquariums measuring 40 x 30 x 25 cm, with a volume of 30 liters each. The seaweed types were tested at a density of 2.8 g/L, while the method employed was a complete randomized design (CRD) with three treatments and three replications. Furthermore, the water for the experiment was taken from the pump of the equalization pond in the super-intensive wastewater treatment plant. The seaweed parameters measured were the final average weight, absolute growth, and specific growth rate. The absorption rate of total ammonia nitrogen (TAN), nitrite, nitrate, and phosphate was assessed with time intervals of 6, 12, 24, 48, 72, 96, 120, and 144 hours. The results showed that the growth of the three seaweed types was significantly different (p<0.05). The highest average reduction rate of total N was found in Eucheuma spinosum and Gracillaria verrucosa plants which were in the “very effective” (VE) category in absorbing total N and PO₄.