and Pond Lights
This is the most common ulcer found on fish in
a koi or garden pond or a fishing lake.
Aeromonas Hydrophila is in fact
a soil bacteria, which is why its so common.
This bacteria is present
in all bodies of water no matter how well kept, but its a secondary invader
which needs to have the door open for it by say parasite infection, fluke,
leeches, fish louse, poor handling (inc netting), sharp objects like rocks and
decking and pond lights.
You should never put lights under water - at
night they attract the ponds poly culture which the fish will eat. However,
when the fish are disturbed they move quickly to escape an assumed predator,
and this in turn brings the fish into contact with the lights.
is mainly the head or the caudal carbuncle - the tails drive muscle. These are
ideal sites for wounds to become infected with this bacteria. See picture of
large goldfish with damaged tail which it caught doing a 90 degree turn - quite
common with light damage.
I find the main course is stress - poor water
and lack of filtration and over