$e ee Tor 
20 THE FRESH-WATER AQUARIUM. 
If there is a bed of two or three inches of sand, the 
roots may be gently pressed down into it, and a few clean 
pebbles laid over the spot to keep the plant in its position. 
Some plants will require a stone to be attached to them by 
means of a thread to fix them properly. Crowns of 
Stratoides that have not formed roots, may be planted in 
this way. First cut away any black or decaying matter 
from the stem, and pull off any discoloured leaves, taking 
care not to injure the centre, then pass a piece of bass 
round the base, and attach a small stone. The plant will 
remain firmly where placed, and will throw out roots, and 
fix itself before the rotting of the bass takes place. It will 
then throw up new crowns and become a very ornamental 
object. Loose stems of Chara, Anacharis alsinastrum, or 
Callitriche, may be gathered together, fixed by means of 
a stone in the same way, a strip of bass being better than 
string for attaching them. They will generally get well 
rooted in a fortnight, and remain firmly where planted. 
The Water should be pure and bright when introduced 
to the tank, and if the supply is at all faulty, it will be 
best to pass it through a filter before using it. Spring 
water will do very well, but must stand a day or two to 
allow the plants to soften it, before the fishes are put in. 
My tanks are all filled with spring water, which I find 
altogether unobjectionable; but for the marie tank I 
think it preferable to any other in the manufacture of 
artificial sea-water. Writers on the aquarium usually 
insist on the use of river water, but in many places this is 
not attainable, and it is satisfactory to know that artesian, 
or well water, will serve the purpose admirably. 
