For future reference, please do not freeze larger fish to death. If they are capable of feeling pain (which I belive they do) then freezing likely to be very painful for the fish. [topic="207212"]This topic[/topic] in the scientific section indicates that the fish remain consious while they slowly freeze from the inside out for several hours before their bodies finaly shut down
IMO, for small fish, a hard knock to the head is the best route to go, very quick, little suffering, and a tidy way of doing things. Clove Oil would be best for larger fish, if you are too squemins to drive a nail/needle into the fishes brain.
HTH
Rabbut