You have been constructing and building your water garden for days or weeks, now
detailing your water garden and controlling the environment for both your koi
fish and your gold fish will be the next most important things on your mind.
Temperatures, light, oxygen levels and even bacteria can affect your fish and
without a little bit of research you could lose your entire fish crop without
much notice. Always be on the look out for problems, even if you only visit the
water garden once a week, at least watching the water and the fish will be a
great start in prevention.
The environment temperatures and the water temperature will affect your fish.
When the colder weather starts to set in, your fish are going to require less
feeding and their metabolisms will slow down. They can live below the ice if
your water garden is deep enough to support their needs. Water gardens that are
not very deep could entirely freeze, killing your fish in the coldest northern
regions.
You fish will continue to feed until the water temperature dips down to
freezing. Even if the top of the water garden is not totally ice yet, the fish
are most likely in hibernation and do not require food.
It is important not to introduce new fish to the water garden when the
temperatures are near freezing as the fish is most likely not accustomed or
prepared for this sudden change which can shock their system and they will die.
If you want to add to your collection, the best times or seasons to do this are
in the early spring or in the early fall months when the water will not be
entirely too hot or too cold for them to be easily accustomed too.
Most fish that are bought in a store, inside in a store, the temperatures of
their water is going to be about sixty or seventy degrees, so you would want to
make sure your garden water is a similar temperature to ensure your best
success.
To be safe when introducing new fish, keep their original water in a bag with
the fish and set the bag in the water garden to slowly change the temperature of
their water so that their body can also adjust to this change.