Sports trainers treat sprains and soreness with ethyl bromide. it is manufactured by reacting ethylene with hydrogen bromide:

Trainers use this substance because the reaction of the product on the skin is an exothermic one. This produces a feeling of warmth and heat. Heating an injury like a sprain with warmth or heat increases blood flow to the area and promotes healing as the flow of blood carries the necessary substances for healing. 

I’d have to say no because without oxygen in the water the fish would all be dead. so if you want to fish for dead fish, pick the ponds with the lowest oxygen concentrations.