On most occasions
temperature will be lowest in the morning just before sunrise and the highest
at sunset. (unless your pond is built on a nuclear waste dump, which
generates it's own heat). Temperature is influenced by the amount
of sun, the intensity of the sun the pond receives and other factors such
as the wind speed during the day or night. Evaporation cools the
water. Generally speaking koi should not be subject to more than
a 3 - 5 degree sudden change in water temperature. Always adjust
the temperature gradually when moving koi around. An upward movement
is tolerated better than a downward movement in temperature. Most
ponds have a 1 - 3 degree C variation in temperature in a 24 hour day/night
cycle. Koi are more affected by temperature variations at lower water
temperatures. And you will notice koi are more affected by a sudden
lowering of water temperature than a sudden raising of water temperature.
Certain areas in the country can experience a 10 - 15 degree C atmospheric drop in temperature
in a a day accompanied by high winds. Ponds can and do drop temperature
significantly in these circumstances. The koi
suffer from stress and
disease problems can occur at a later date. In some cases the koi
can catch a "cold". A white film is seen in the skin. The thin
flesh around the head is the area where this is most visible. Should
the temperatures rise within the next few days the "cold" will cure itself. However, this may
take some time.
The koi can be helped
through large, sudden water temperature changes by the addition of a good
grade coarse salt at a rate of 1 - 2 kg/1000 litres immediately after the
temperature has dropped.
