146 GOLDFISH VARIETIES AND 
final change from salt back to fresh water, this is a very good way to 
accomplish it. Dripping water may do all that is necessary, especially if 
a fish is only on the doubtful line, which is more often the case than not. 
Summer offers one more treatment when all others fail—place the 
affected fish in a shallow mud-bottom tank or pool. This is especially 
beneficial to goldfishes. 
In winter when a skilled aquarist finds a fish a little out of condition, 
but with apparently nothing radically wrong, his first treatment is to 
remove the fish to another tank if he has one available. This often has 
the stimulating effect of a change of climate and usually wards off more 
serious trouble that might be developing. As with ourselves and all 
animals, it is much better to cure an ailment, if possible, by improved 
conditions, rather than by recourse to drugs or chemicals. 
In treating sick goldfishes it is important to give some attention 
to temperature, especially in winter. Best results can be had at about 68°, 
which is a little warmer than fishes are usually kept in the cool season. 
Another point to bear in mind for those having air-pumps, is that 
in the majority of ailments a cure is accelerated by a gentle flow of air 
liberated in the hospital tank, but not agitating the water enough to worry 
the fish. If no pump is at hand an occasional spraying is of value. 
The foregoing is general in character but will be found useful in 
most of the diseases that can be cured. We will now deal specifically 
with the diseases and ailments. 
Fin Congestion. This is the commonest of all fish troubles, and is 
especially liable to attack the highly developed fins of fancy goldfishes. 
Their long fins are no doubt deficient in circulation, causing low powers 
of resistance. As soon as the fish is slightly indisposed through over- 
feeding, sudden chill, protracted low temperature or other causes, fin 
congestion is ustially the first symptom. The fins of fancy goldfishes 
may be considered very good barometers of the condition of the fish. 
The appearance produced is well indicated by the name. The fins are 
more or less red and streaked with veins. In advanced cases the fins 
commence to split and fray, particularly the tails. 
TREATMENT. Fin congestion, as well as being the commonest of gold- 
fish diseases, is also the most easily cured. The salt-water treatment 
described on page 144 is without a superior. When the trouble is con- 
fined to the tail, it may be dipped in a 10-per cent. solution of peroxide 
of hydrogen. Another method is to paint the fish with coal oil, keeping 
the head and gills wrapped in a moist cloth. Usually lighter feeding and 
plenty of room in fresh water will be all that is necessary if taken in time. 
Two grains of permanganate of potash to the gallon of water is a suc- 
