Suitability Analysis of Pond Ecosystems on the East Coast of Sidoarjo for Seaweed Cultivation on Productivity, Quality and Carrageenan Content of Gracilaria sp

Gracilaria sp. is seaweed that produces agar and carrageenan, which is needed by the food, pharmaceutical, textile, and cosmetics industries. The high demand encourages cultivation. This study aims to determine the suitability of the pond ecosystem on the east coast of Sidoarjo for the cultivation of Gracilaria sp. The research was conducted in a pond in Kupang Village, Jabon District, Sidoarjo using in-situ observational methods. Water samples were taken from the Aloo river and ponds, samples from Gracilaria sp. taken purposively at 3 stations, namely station 1 Dusun Tegalsari, station 2 Dusun Kali Aloo, and station 3 Dusun Tanjungsari. The parameters measured include land suitability (temperature, pH, salinity, water Cd concentration), and Gracilaria sp. Productivity (carrageenan content). Analysis of Cd concentrations using the Atomic Absorption Spectrophotometer method. Analysis of carrageenan content using the Kjeldahl method. Data of Cadmium concentration analyzed descriptively qualitatively and compared with SNI 7387: 2009 and Kepmen LH No. 51/2004. The results showed that the pond ecosystem on the east coast of Sidoarjo was suitable for the cultivation of Gracilaria sp., Gracilaria sp. yields met the quality standards where the Cadmium concentration was below the quality standard threshold, the carrageenan content was moderate.