Evening star., 1934-08-04
THIS AND THAT
BY CHARLES Z. TRAcEFELL.

Next to correct feeding. the greatest
problem In amateur fish keeping Is
that of green water"
He who invents some sure-fire and
harmless non-chemical method o.
preventing this state Of affairs and
also OF breaking 1t up after 1t has
formed will earn the undying graft
tude Of thousands OF persons.
Green water" Is simply aquarium
water in which the so-caIled free
living forms Of green algBe have null
tiplied to the extent that the water
becomes haxy and the fishes obscured.
The really distressing thing about
IL Ia that such water Ia not at all
harmful 10 the animals. but rather
good for them. IL anything.
II green water" were harmful the
aquarist would be forced to empty
the tank and begin all over again. but
since 1t Is n natural state often found
in pools in the warm season. he finds
himself willing to go to that extent
only as q last resort.
He wonders IL green water" really
Is good for the fishes. after all. as he
has 50 often been told He permits
the condition TO 20 on. daily becom-
ing thicker and thicker, the fishes
hourly more invisible.
He finds that one or two inmates.
maybe suffering from slight touch
Of fungus on the tail. rapidly become
clean again, for he still can see
easily enough when the swimmers
come close 10 the front glass.
The microscopic plants which cause
this green give of a certain amount
OF oxygen. that is mainly why they
are a healthful influence In the wa
ter. That Is not the only reason,
however. Perhaps the main thing
they do is to absorb surplus food.
especially the very tiny particles
which unfortunately are a part Of
most OF the prepared flsh foods.
1t is believed that these forms Of
minute life cannot get a start unless
tiny bits OF food are floating in the
water, disdained by the fishes, and
not yet IN a form where they can be
utilized by the major plant life OF the
aquarium.
Correct feeding, therefore, Is the
real solution to the green water"
problem, but this is q solution more
theoretical than practical, because no
matter how carefully one feeds the
tank inmates there may come time
when the surplus bits of food pile up.
The trouble is that the aquarist, no
matter how learned, does not know
wnen this time arrives. There is no
certain way for him to be sure. Down
in the back OF his mind, however, he
will have q sneaking idea. after a
tank begins to go green, that he put
in too much food the other day. The
little fellows were exceedingly hungry
and he needed the importantly of
their rapid swimming. BY wiggling
to and fro, aquarium fishes say as
plainly as you please. 'Morel More!'
Even the experienced keeper Of
small tropical fishes often succumbs
against his better Judgment, to the
pleadings of his small charges for
just little bit more dinner, please"
Nor has he any certain way of de-
termining which particular foods are
liable to cause this condition to start.
He may think, at times. that he has
isolated the culprit. but then he will
realize that several other tanks, in
which he used the same food, are as
clear as ever.
A newly planted tank is most liable
to become green. especially an aqua
rum in which the water Is new and
which perhaps contains too many
fishes per gallon OF water.
The theoretical rule is an inch OF
fish to the gallon of water. This is
the old standard rule for goldfish,
tested and tried for many years by
people the world over. Two gallons Of
water per inch Of goldfish is better.
There would be comparatively little
failure with these interesting animals