THE FRESHWATER AQUARIUM AND ITS MAINTENANCE 



height than 22 inches is objectionable. For out-of-door tanks and cis- 

 terns, any size and a variety of materials may be used; but when built of 

 wood, they should be seasoned by a frequent change of water. Slate, soap- 

 stone and cement basins are used, of which more will be stated hereafter. 



Arranging the Aquarium. The aquarium should be set on a stable 

 support, a stand, table or shelf, preferably facing a northern or north- 

 eastern exposure in the summer, while in the winter it should be placed 

 to get the sunlight two or three hours daily, preferably the morning sun; 

 as it is essential that the aquarium should get a good light or failure will 

 be the inevitable result. If indoors it should be placed at a window or 

 under a skylight admitting the daylight and sunlight but without too much 

 exposure to the direct rays of the sun during the hot summer months. 

 The best success will be had when the light is such as to stimulate the 

 growth of the plants without producing material changes in the tempera- 

 ture of the water. The position at a window also permits of the necessary 

 ventilation and aeration; the slight draught, even when the window is 

 closed, is a protection from excess of coal or illuminating gases and tobacco 

 smoke; and in warm weather, it will moderate the temperature of the water 

 if the direct rays of the sun are excluded. 



Covers for Aquaria. Experts advocate glass covers for the aquarium 

 having sufficient plant life. The plants will grow more luxuriently, dust 

 will be kept out, froth and bubbles will not form on the surface, and the 

 evaporation will be less rapid. The cover need not fit tightly, but raised 

 about 54^ inch by rubber or cork discs on the upper frame of the aquarium 

 or it may have the corners cut away. The cover will also prevent the 

 single-tailed goldfishes, the ide, tench and other freshwater fishes, from 

 leaping out of the aquarium, a habit which they have inherited from their 

 wild congeneters who do this at twilight, when the day enemies have retired 

 and those of the night not yet appeared. The double-tailed goldfish can- 

 not leap from the water. Wire gauze or cotton netting over the top of the 

 aquarium will also serve to prevent the leaping out of the fishes. 



Aquarium Equipment. In the equipment and maintenance of an 

 aquarium cleanliness is the all-abiding law. The interior should be cleaned 

 with water, the glass rubbed with table salt, either on the finger tips or on 

 a soft rag, and then carefully rinsed; no soap or alkaline substances are to 

 be used nor any greasy or soiled vessel employed. When placed in posi- 

 tion, the bottom should be covered with two inches of well washed sand 

 or grit, (small pebbles) and covered with small or larger pebbles; this depth 

 being requisite for the proper rooting of the plants. 



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