Chlorine is the fish killing agent. First dissolve the powder in water and then broadcast over the pond surface. Calcium hypochlorite is a solid powder. It can burn the lungs if inhaled. A filter mask should be worn or breath held until the powder is safely in water.
Ammonia is the agent affecting fish.
Farming of prawns and shrimps. Extension Manual No. 5. Fish and Fisheries of India. Hindustan Publishing Corporation, Delhi, India. V.G. Jhingran and R.S.V. Pullin, 1985.