MANAGEMENT OP THE AQTJABIUM. 



57 



one to be inserted in the tubing of the pump at g, and the 

 other at /. If there is a difficulty in putting a trap so far 

 down the tubing as /, the latter must be cut through at that 

 point, and joined again by placing each extremity of the cut 

 part over opposite ends of the trap. When this has been 

 done, the junction shotild be made quite secure. by covering it 

 three or four times with the indiarubber solution. When this 

 pump is used, the longer tubing is put 2in. or Sin. deep in the 

 water, while the shorter is held over it ; and as the ball is 

 repeatedly and vigorously squeezed, an almost continuous 

 stream of water will run out of and back into the aquarium. 

 The trouble of making the traps 

 may be prevented by substituting 

 two of the glass tubes which are 

 made for babies' feeding-bottles. 

 These tubes are trapped. 



A piece of sponge fixed in the 

 hole of a flower-pot will make a 

 kind of filter. The sponge should 

 be so tightly packed as to allow 

 the water to run through the hole 

 slowly in drops only. This simple 

 contrivance can be either suspended 

 over the aquarium or placed on 

 two strips of wood resting on the 

 top of it at the centre. It may 

 also stand on the cover of the 

 tank if that be strong enough. 



Fig. 42. Top op Flower-pot 

 Filter, showing Wire Frame 

 for holding in position Pot 

 containing Plant. 



Of course, if the cover 

 is glass, a hole must be cut through it, to allow the water 

 to run from the filter into the tank. Should the fiower- 

 pot be something better than a common one, and another, 

 in which some pretty semi-aquatic plant is growing, is 

 placed inside it, the arrangement will be both useful and 

 ornamental. A little water, taken occasionally out of the 

 aquarium by means of a small siphon and put into the filter, 

 wiU cause an almost constant drip of water into the aquarium. 

 The pot containing the plant is kept in its position in that 

 which is acting as a filter by means of a small wire frame. 



