Before killing, the fish can be starved up to 3 weeks to remove undesirable oil deposits as commercial fish feed is very high in oil and it will be less messy to take out the insides of a fish. If it is not wielded effectively, the fish may simply be injured, possibly losing a eye in the process. The ice, meant to keep the carcass fresh, causes the fish to remain conscious for longer. Thus, suffering is prolonged. Fish such as plaice will desperately cling to life for hours out of water and may well be filleted alive.
Countless fish die even before they reach the pet store.
Capture alone injures and kills millions of fish when they are incapacitated by anaesthetics, dynamite or cyanide before being caught by hand or net. Keeping a fish in captivity disregards its most basic instincts and is incompatible with their fragile and high-strung nature. Fish are more sensitive to temperature than any warm-blooded animal. A sudden change of only a few degrees can kill a fish. In small containers temperature can fluctuate very quickly.