History: 4 hours after draining a koi pond
all its occupant were dead.
Presentation: a. 3 recently dead koi fish
b. water sample
Water analysis:
a. Total Ammonia= 0 mg/l
b. Dissolved Oxygen= 7.2mg/l
c. nitrite=0mg/l
d. Alkalinity= 120mg/l
e. pH= 7.5
f. total hardness=105
Fish Necropsy:
a. Gill Biopsy-few trematodes;
gas emboli visible in gill
capillaries
b. Skin Biopsy-normal
Conclusion:
Gas bubble disease- the history is
typical husbandry error filling a
pond with a hose and allowing the
end of the hose to submerge. This
traps gases in the water column and
gets pass to the fish. Simply
spraying the hose to the side and
letting it run down would have
prevented this problem.
