Replace the plants and animals, reserving those pieces of rock, or those shells, which look suspicious, which may be kept in a bowl of water by themselves for a few days, till their state appears more fully.
This process of bringing every drop of the water into contact with the atmosphere, is an effectual remedy for destroying the tendency to putrefaction; as the animal fluids and solids held in suspension enter into combination with the oxygen of the air, and form the pure innocuous gas called ozone. The result will be that the milkiness will rapidly disappear; the water will assume a transparent clearness, which will in all probability be permanent; the plants will thrive, and the animals will be lively.
Occasional Death.—It will still be needful to exercise a watchful supervision of the collection. It must be remembered that both the animals and plants are not in their natural circumstances, and that a certain amount of violence is done to their habits. Death, which spares them not at the bottom of the sea, will visit them in the Aquarium; and hence the vessel should be occasionally looked over, searched, as it were, to see if there be any of the specimens dead. If the plants show the orange hue, already spoken of (See ante, p. 25), they must be taken up, and the diseased parts cut clean away. Dead animals must be at once removed, or contamination will soon result. The eye will soon recognise the individuals, and will miss the familiar forms; but you must not too hastily conclude that an animal, which you have been accustomed to see playing about, is dead, because you have not observed it for some days
