
AILMENTS AND DISEASES 

intervals until by evening all has been introduced. After about two-thirds 
of the solution has been added, careful attention must be given to the fish, 
and ifits condition is weak and the indications are that it would be endangered 
by a stronger bath, it should be removed to the second vessel, the water of 
which has been aerated by frequently dipping out and pouring back. It 
is necessary to leave the fishin the solution as long as endurable without 
complete exhaustion indicated by excessive restlessness and later by partly 
or completely turning on its side. Should the fish not recover at once in 
the second vessel, it must be kept in motion by gently stirring the water. 
Picric acid has also been found to be beneficial. A  one-percent. 
solution of this poisonous acid is made in hot water. The fish is placed 
in well-aerated water to which small quantities of the solution are added, 
until zs to goes part of the acid is present in the water, if the fish can endure 
this amount, and then, after a few minutes, water of the same temperature 
is added at intervals until a very considerable dilution has taken place, when 
the fish should be removed to well-aerated water. This may be repeated 
after a few days, the fish to remain in the weakened bath several hours, if 
possible. Chlorate of potassium is used in the same manner, but the 
amount present in the water should not exceed 1 in 1000. All three of 
these remedies are certain to destroy the higher forms of surface parasites, 
and usually those encysted on the fish. 
American breeders have successfully applied the following remedies, 
all of which are to be recommended:— 
Permanganate of potassium solutions are powerful disinfectants and 
frequently used specifics, but are not always efficient. They produce an 
objectionable discoloration of the water and when sufficiently strong to 
destroy the parasites cannot be endured by the fishes. The best applica- 
tion is by the use of a separate vessel, and covering the mouth and gills 
of the fish with a wet cloth agitating the body in a strong solution for a 
few minutes, then placing the fish into water to wash off the potassium 
before returning it to the hospital jar. 
Bichloride of mercury has been found to be beneficial when applied 
in the same manner, also a weak solution of formalin; a tablet of the former 
in a pint of water and a Io percent. solution of the latter. Salt is a gener- 
ally applied and safe remedy, and should be used as previously mentioned, 
a strong solution kept from the gills, and a weaker one by placing the fish 
into it for one or more days. 
External applications of boracic acid in water have proven effectual 
for surface parasites, and should be frequently applied with a brush or a 
pledget of cotton. Very satisfactory results have been obtained with a 
50 percent. solution of peroxide of hydrogen in water. The fish is grasped 
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