MARINE AQUARIA 



nected with the aerating device, for the breeding of these low forms, and 

 containing a marine plant or two; from which they are dipped with water, 

 but this is not imperatively necessary. Other and larger animals should 

 be furnished with more substantial food, the preferable dietary being finely 

 scraped lean beef and mutton, minced angle worms, and small particles of 

 oysters, fish and crab-meat. Tweezers or feeding rods are required to 

 place the food in, on or near the molluscs, anemones and other polyps, 

 which should be fed once a week; but the small crabs, starfishes, other 

 higher forms, and the fishes, should have the same food, given them at 

 intervals of two or three days. Great care must be exercised that all the 

 food is consumed, as its rapid decomposition will cause water contamina- 

 tions. If any remains uneaten, it should be at once removed with the 

 dipping-tube. The partly digested or rejected food fragments, given off 

 by the lower animals and the skins of the polyps, should also be removed. 

 Careful sanitation is as necessary with the marine as with the freshwater 

 aquarium; even more so, as the scavengers of the sea are not as efficient as 

 those of freshwater. 



Anemones should be sufficiently fed or they will become dissatisfied 

 with their positions and move about to find a more desirable situation. 

 The food should be placed on the end of the feeding stick and the tenta- 

 cles lightly touched with it, several very small pieces being offisred to the 

 same individual. If they are rejected the anemone is not hungry, as it has 

 the power of making its tentacles adhesive, or not, at will. Some forms 

 kill their prey by acontia, small threads and spikules with stinging cells, 

 which they give off at will. These should have the food brought directly 

 into the centre of the disc, for if the tentacles are touched they will im- 

 mediately collapse. When hungry, they will at once engorge the food, if 

 not, it will be rejected and should be removed. The water in the vicinity 

 of anemones should also be stirred occasionally. 



It should be noted that the food requirements of marine animals in 

 the aquarium are less than in natural surroundings, which should be con- 

 sidered in feeding, and that they take more food ivhen the water is warm 

 than when it is cold. 



Stocking the Aquarium. Overcrowding is as objectionable in the 

 marine as in the freshwater aquarium. Not more than one inmate of any 

 kind to the quart of water should be introduced, or less according to the 

 existing conditions and the kind and size of the animals. Overstocking 

 is one of the most frequent causes of discouragement and failure to the 

 novice. It should be remembered that marine aquaria are to be admired 

 as much for the artistic arrangement of the inanimate objects they contain 

 as for the wonderful and varied forms of marine life; and a few healthy and 



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