AQUARIUM. 



253 



Under the Auspices of The Aquarium Society of Philadelphia, Herman T. Wolf, Editor 



The Household Aquarium and Its 

 Inmates and Management. 



COPYRIGHTED BY HERMAN T. WOLF, 



AUTHOR OF "GOLDFISH BREEDS AND THE 



OTHER AQUARIUM FISHES." 



PART II. 



Aquarium Plants. The purpose of 

 aquatic plants in the freshwater aquarium 

 is not only to add to the beauty of this 

 miniature water garden but also to ful- 

 fill important functions in maintaining 

 an equilibrium or balance, so that the 

 animals will live in comfort and the 

 aquarium be virtually self-sustaining, as 

 is the natural aquarium, the pond and 

 stream. 



The oxygen necessary to sustain the 

 life of aquatic animals is not that which 

 forms a chemical constituent of water, 

 (H2O), but that which is in the air 

 dissolved or held in suspension in the 

 water. In ponds and streams, the wave 

 motion on the water surface supplies the 

 greater part of this suspended or dis- 

 solved air, but in the confines of the 

 aquarium, surface aeration is insuffi- 

 cient and air must either be artifically 

 admitted or furnished by the breathing 

 of aquatic nlants. 



As stated in the previous article, plants 

 in their growth liberate oxygen and take 

 up the carbonic acid gas given off by 

 the living creatures ; and the animals, in 

 their turn, require the oxygen and give 

 off carbonic acid gas ; so that if the plant 

 and animal life is in balance, the quality 

 of the water will remain nearly the same 

 for long periods. It is better, however, 

 to have a preponderance of the oxygen 

 liberating element present and only as 

 much animal life as will live in comfort. 

 The olants which best perform this 

 function have been mentioned ; it is now 

 in order to brieflv describe them that 



they may be recognized; which will be 

 done in the order in which they best per- 

 form this duty. 



Arrowhead or Sagittaria. A small 

 genus of variable plants, reduced by 

 Micheli to 13 species; perennials of easy 

 culture, propagated by seed and runners 

 and growing on the muddy bottom of 

 ponds and streams. 



They have arrowshaped leaves and 

 small buttercuplike flowers, which reach 

 above the surface of the water. In 

 rapid streams the leaf blades are changed 

 either to the form of a spade or length- 

 ened into limp ribbonlike floating bands, 

 which extend above the water only in 

 the flowering season. Some of the 

 species develop broader floral leaves and 

 are submerged at other seasons. These 

 are Sagittaria natans and S. pusilla, one 

 broad and the other narrower leaved, 

 and 5". sinensis or 5\ gigantea the giant 

 aquarium Sagittaria. They may be had 

 of dealers. The first two are the best 

 of all oxygenators, the latter also good 

 but more likely to grow above the water 

 surface, when its active and beneficial 

 function ceases 



Eel grass or Vallisneria. A single 

 universally distributed species also known 

 as Tape-grass or Wild celery, Vallis- 

 neria spiralis, which grows in fresh, 

 brackish and salt water, from a rooted 

 tuft, having the bluntly pointed narrow 

 leaves of the same width their entire 

 length, one to ten feet long, dependent 

 upon the depth of the water. The young 

 plants are most likely to survive in the 

 aquarium. May be found in almost 

 every stream or can be had of dealers. 

 The cultivated variety, V. spiralis gigan- 

 tea, having V 2 inch broad and 3 feet long 

 leaves is more generally used by expert 

 aquariists. 



