Shock commonly occours when there has been too abrupt a change in one or more of the environmental factors. Fish most likely to suffer from shock are those that have been newly introduced to an aquarium although fish can be subject to shock following a partial water change if insufficiant attention was paid to matching the water conditions. There are three main causes of shock;
Temperature shock is caused by a sudden change in the temperature, with a decrease causing more severe shock.
Toxic shock is caused by sudden exposure to high concentrations of Ammonia, Nitrite or NITRATE. Nitrate Shock often takes some time to manifest any symptoms (24-72 hours) and is often fatal.
Osmotic or chemical shock is common after a sudden change to the water chemistry, commonly, hardness, pH or salinity. Symptoms take 24-72 hours to manifest, this type of shock is often fatal. See Osmoregulation.
Abnormaly fast or slow gill rate, resting on the bottom; See Bouyancy, loss of Appetite, Clamped Fins, abnormal pale Colouration, with severe shock the fish may lie on it's side or belly up.
Serious shock is often fatal so should be avoided. In the case of temperature shock removal of the newly introduced fish should be carried out into more congenial water conditions, re-introduction must be carried out carefully after matching the water temperatures. With delayed shock caused by toxins, chemicals or osmotic any attempt to rectify the problem will often be too late to save the affected fish, any further adjustments must be made gradually in order to prevent the resident fish going into shock too.
Back To Breeding Tropical Fish