Uji Laboratorium Bioaktivitas Antifeedant Ekstrak Kasar Timun Laut Synapta maculata (Chamisso & Eysenhardt, 1821) dari Perairan Pulau Kotok Besar, Taman Nasional Kepulauan Seribu, DKI Jakarta terhadap Ikan Gymnocorymbus ternetzi (Boulenger, 1895) = Laboratory Test of Antifeedant Bioactivity Crude Extract of Sea Cucumber Synapta maculata (Chamisso & Eysenhardt, 1821) from Kotok Besar Island, Seribu Islands National Park, DKI Jakarta on Gymnocorymbus ternetzi (Boulenger, 1895) Fish