Page:The Book of the Aquarium and Water Cabinet.djvu/107

Rh reviving exhausted stock is wholly or partially to change the water; with marine stock, such a change is not easy, and the filter comes more legitimately into use. As already remarked, the necessity for aeration marks error in management, except when you have stock for which no proper receptacle is at hand, or any such special contingency.

Decay of Plants.&mdash;The sea-weeds are apt to acquire a pale tint, which is the first evidence of decay. This generally happens with the first marine stock, when Ulva and Enteromorpha are used to season artificial water. When the water gets ripe, the plants recover and make healthy growth, but if many white fronds appear, lift out the blocks on which the plants are fixed, trim away the decayed portions with a pair of scissors, and then scrub the stones with a small brush in a little waste sea-water, and replace them; they will soon recover. If red plants have been hurriedly introduced, and decay manifests itself, remove them at once, and waste no time in attempts at revival. Mr. Lloyd will supply a new stock for a trifle, and it is better to begin de novo than to attempt to cure the incurable.

Death of Anemones.&mdash;If you observe any of the anemones to shrink up like button-covers, lift them out into a shallow vessel, and aerate them liberally. When small beads of gas appear upon them, you may rest assured that they have gone beyond the&mdash;

for the first outward proof of death is the formation of