The effect of volcanic ash from the eruption of mount Sinabung on the survival and tissue structure of Mahseer fish (Tor tambroides)

Volcanic ash of Mount Sinabung enters the Lau Borus River. One biota in river that is affected by volcanic Mahseer fish. This study aims to determine LC50 from exposure fish, water quality, and tissue histology The concentrations for toxicity tests were 0 mg/L, 66,000 87,000 115,000 152,000 mg/L. results probit analysis showed values at time 24, 48, 72, 96 hours 135,249 106,741 72,210 68,798 respectively. higher concentration given will accelerate death followed damage skin, gill intestinal tissue. There muscle necrosis epidermis thinning skin. In gills there hyperplasia, hypertrophy, fusion, cells. Hyperplasia hypertrophy goblet cells, villi intestine.