The metabolism
of koi
and goldfish
is controlled
primarily
by water
temperature.
As the
water
cools,
pond fish
require
less protein
in their
diet.
When koi
and goldfish
are fed
high-protein
food in
cool water,
the excess
protein
is excreted
as ammonia
from the
gills.
The microscopic
organisms
that make
up the
biological
filter
(and consume
ammonia)
also slow
down in
cooler
water
.
Improper
seasonal
feeding
can lead
to a build-up
of toxic
ammonia,
which
stresses
fish and
reduces
their
winter
survivability.
When the
water
temperature
drops
to approximately
65° F,
start
feeding
with Spring
& Autumn
Pond Food.
This type
of fish
food is
better
suited
for the
dietary
requirements
of pond
fish in
cool water
and won't
pollute
the water
with excess
ammonia.
Some water
gardeners
continue
to feed
their
fish until
they no
longer
come to
the surface.
I stop
feeding
my pond
fish when
the water
falls
below
42° F.
There
is no
need to
worry
about
"frozen
fish"
if a section
of the
pond is
at least
18 inches
deep.
Pond fish
will seek
the deepest
part of
the pond
and over-winter
there
until
the water
warms
in the
spring.
If your
pond is
less than
18 inches
deep,
the fish
may freeze
during
a harsh
winter.
Check
with your
local
pond supplier
if you
live in
an area
with harsh
winters.
Some water
gardeners
with shallow
ponds
attempt
to keep
their
koi and
goldfish
in kiddie
pools
or aquariums
set up
in a cool
basement
or garage.
This is
not recommended
because
of the
extra
stress
involved
in netting,
transporting,
and re-acclimating
the fish
to the
new environment.
\
However,
if you
dont have
a choice,
and need
to bring
your fish
inside
for the
winter,
be sure
to have
an aquarium
air pump
or small
fountain
to provide
oxygenation.
The fish
should
be fed
infrequently,
if at
all, depending
on the
water
temperature.
pH, ammonia
and nitrite,
which
should
be monitored
weekly
and especially
if the
fish are
fed.
Small
water
changes
(20%)
each month
will keep
the water
in good
shape
until
spring.
Koi are
"jumpers"-so
be sure
to cover
the pool
with bird
netting!
