to  fail  and  at  the  best  to  be  a  holding  exercise  in
‘hobby-horse’ terms, you are flogging a dead horse!
Where do you start finding answers? Whenever you
face fish health problems it is important to question
everything but that is another article! For now let’s
stick to metals. How do metals enter the pond?      The   simplest   method   is   by   inappropriate
construction materials the koi keeper installs.      A  very  important  question  is,  Does  your  pond
water  come  into  contact  with  metals?  Have  you
used a run of copper pipe? Have you bought some
garden ornaments to use for a water return to the
pond which have a copper or lead pipe? Do you use
a central heating pump made from iron? Do you use
a  brass  float-valve  for  automatic  top-up?  Do  you
heat the pond water in the winter? Fine! Does the
boiler have a copper heat exchanger? Construction materials must be fish safe and must not leech metals      Do you use any metal containers for anything? If
so what is the metal? Dependent upon grade, even
stainless  steel  can  leach  metals  into  the  water  it
holds.  What  about  the  solder?  Is  the  solder  made
from lead?      Do you use a garden water butt to store water?
Is it made from food grade plastic or does it leach tin? Ridiculous? Not at all. Many koi are reported to
have died in Europe because they were kept in eel
vats made from a plastic which leached tin.      What grade plastic piping do you use to circulate
water for the pond? Again, some can leach various
metals. Sometimes a number of small metal items
can  have  a  cumulative  effect.  Sometimes  it  is  a
single item, e.g. in a hard water area, a koi keeper
added a fairly short  (c. 5 - 6 foot) copper pipe run to
the  pond  and  started  to  experience  koi  health
problems.  The  copper  pipe  was  replaced  with  an
appropriate  plastic  pipe  and  the  health  problems
cleared up. As hard water tends to lessen the effects
of  metals,  it  is  likely  that  a  similar  copper  pipe
installation  in  a  soft  water  area,  would  have  had
greater adverse effects on koi health. Tap W ater , finding the amount  of metals        in the water and reducing it for koi.
While  you  are  rushing  round  ticking  off  your check list of potential metals ‘adders’; don’t forget
to telephone the water company for a copy of your
drinking water report. (The telephone number is on
your water bill.)      The  vast   majority  of  water  companies  are
extremely helpful if approached in the right way. If
you do find it difficult to get a report then telephone
The  Drinking  Water  Inspectorate  based  at  The
Welsh Office in London (this should be last resort).
The  metals  you  need  to  check  on  the  report  are
aluminium, copper, iron, lead, manganese and zinc.
You  will  see  three  columns  of  readings  for  each
metal; minimum, mean (or average) and maximum.
Some  water  reports  have  fairly  similar  readings
across  all  three  columns.  Some  reports  can  show
huge swings between the minimum and maximum
reading for a particular metal.      To  see  whether  you  are  likely  to  have  the
maximum reported metals in your tap water, start
asking yourself questions again. Are you on an old
private iron mains? Is your house fairly new or have
you just had new copper pipes instal