THE EBESH-WATER AQUAKIUM. 87 



for that reason it is always best not to give the fish all 

 that they will take, but rather keep them on short com- 

 mons, as 1 have observed minnows and son-fish to stuff 

 themselves with food until it projected from their mouths 

 and then, afterwards, eject it and allow it to decay in some 

 out of the way place, where we would not be likely to see it 

 until it was too late and damage had been done. Mr. Ilib- 

 berd recommends cheese as good for fish. I have found 

 that sun-fish eat it, but only when very hungry. 



The snails will often do their work insufficiently, and 

 then the glass will become cloudy with conferva. To re- 

 move this, I use a piece of sponge tied to the end of a 



t-ponge. 



stick, and rub it across the glass. Some writers mention 

 an old nail-brush as answering the same purpose, but it 

 cannot be introduced and used so easily as the sponge. 

 With all our care, no doubt, it will be found almost neces- 

 sary to empty the tank once a year and thoroughly clean 

 it ; but, still, this should never be done, unless the soil at 

 the bottom has become black and the plants show signs of 

 decay ; then, only, we should remove our live stock by 

 means of a net, made by stretching a bag of bobbinet 

 over a wire ring and carefully placing them in a vessel of 

 clean water until the cleaning of the tank is complete. The 

 plants are, then, also removed, as are the water and soil. 

 It will be found preferable not to use the same soil again, 

 as, with all our labor, it will be found very difficult to per- 



