color change

[David L Crawford]

I have a koi that is ~2yrs. old and 10". This fish has been pure orange
for as long as I've raised him (~2'). Now in the last few weeks there is
a growing patch of black. It started as a dot and now is the size of a
nickel. I understand that fish change color. Where does this sort of
thing end up? Is there a typical progression/outcome that can be
predicted?

David

[dr-...@execpc.com]

It is more likely that the black patch is the healing of a burn site due to
an ammona/nitrite spike. Koi rarely get black after adulthood. check your
water parameters, do water changes, add a little salt. Check the gills,
cause they are often damaged by poor water quality. Solo

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
dr-...@execpc.com
microbiology/immunology/virology
List Manager: Puregold Goldfish List
for care of goldfish go to http://puregold.aquaria.net/
Solve the problem, dont waste energy finding who's to blame
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

[David L Crawford]

About two months ago I had a lemon drop into the bio-filter output and shut
down
the air and water flow for ~1.5 days. When I came home all the fish were on
the
top of the pond gasping for air. The next day the only loss was my favorite
blue koi. I'm sure there was some chemistry change, but everything went
back to
normal so quickly I didn't do any testing. If this spot is a burn site, is
there anything that should be done (besides keeping the lemons out of the
filter)?

David

[dr-...@execpc.com]

When things shut down, it is always the lack of aeration that is first to
affect the fish. In general, it is the biggest fish that dies from a lack
of oyxgen. A lemon is unlikely to affect anything. What color change are
you talking about? So sorry for your loss. Solo

David L Crawford <dlcra...@home.com> wrote:
About two months ago I had a lemon drop into the bio-filter output and shut
>down the air and water flow for ~1.5 days. When I came home all the fish were on
>the top of the pond gasping for air. The next day the only loss was my favorite
>blue koi. I'm sure there was some chemistry change, but everything went
>back to normal so quickly I didn't do any testing. If this spot is a burn site, is
>there anything that should be done (besides keeping the lemons out of the
>filter)? David

[Lorraine]

Hi David. I've been breeding Koi for 18 years now and that is one of the
reasons why I like them so much. It's because they can continually change
from the time they are one to seven years old. You just never know what you
are going to end up with when you purchase a young fish.
Now, in saying that, there is also other reasons why fish get black on them
and there could be a problem with your fish called black spot disease. I
have found that if water conditions aren't quite right and if the fish
happens to hurt itself in some way, black spots will appear on the fish.
Once the conditions in the tank start to improve, the black spots can be
seen to disappear.
If you suspect black spot, try holding off on the feeding of your fish for a
few days, check the bio-filter, make more frequent water changes and see if
the black spot doesn't disappear.

Lorraine