164 GOLDFISH VARIETIES AND 
AQUARIUM PLANTS 
Whether aquaria are kept for scientific study or for the enjoyment 
of the beautiful, aquatic plants will always be found a useful—if not in- 
dispensable—adjunct. The fact that plants give off oxygen under the 
influence of light has been mentioned at several other places in this 
volume, but the principle is so important that it would be difficult to over- 
emphasize it. Aquaria containing good plant growth may be tightly 
covered and if placed in a good light they will support a fair number of 
fishes, the life-giving oxygen being supplied exclusively by the plants. 
That the roots of healthy aquatic plants absorb the products of 
decomposition in the bottom of the aquarium is an established fact. When 
an aquarium has been established for some time, the sand has become a 
little dirty and the plants have spread so that the roots of some are 
against the glass, a close observation will show a condition similar to that 
pictured in figure 114. The sand near the roots is distinctly whiter than 
that beyond their reach. 
No arguments need be put forward 
to establish the esthetic value of plant life 
in the household aquarium or the pool in 
summer. Without them no one could 
attempt to reproduce the effects of - 
Nature. So well understood is the value 
of aquatic plants that aquarists are con- 
stantly on the lookout for anything new 
which might enhance the beautiful results 
already achieved. Occasionally something 
of real merit is found. We are pleased 
to be able to list several of these newer 
Fic. 114. ApsorPtion sy Prant species here, together with all the better- 
Roots known favorites. Only those plants 
having been proven satisfactory are de- 
scribed, but naturally in such a large range it will be found that the same 
conditions are not suited to all. 
It is a good general rule to select young plants. They transplant 
better and sooner adapt themselves to new conditions. If old plants are 
used the dying leaves should be removed. 
Much discussion has been brought out as to the best methods of 
planting, principally as to whether to use soil, sand or pebbles, or whether, 
in some cases, planting is necessary at all. Success has been attained in 
