FOOD AND FEEDING 



between the plants and more clean catches made than with the mull net. 

 The tank should be prepared with a layer of garden soil mixed with a 

 little liquid manure covered with pond mud, on this a thin layer of dead 

 leaves, and then filled with water to reproduce pond conditions. Some 

 algae, voucheria, wolffia and other small aquatic plants will be introduced 

 with the pond mud; and, after stocking, in a short time colonies of shell 

 insects, flea lobsters, water multipedes, infusoria, algae etc. will develop 

 which should be occasionally replenished by catches in the ponds. 



In a small way a candy or battery jar containing a little pond soil 

 and rooted plants, preferably anacharis, will serve; but with ponds or 

 ditches nearby, the mull net will usually be all that is required. Care 

 should be exercised to prevent introducing predaceous insects and their 

 larvae, parasites or other enemies together with this food. 



Preserving Natural Foods. It is the practice of breeders to collect 

 the entomostraca in quantities when they are plentiful and preserve them 

 in a dried state for periods of scarcity. This is done by dipping them 

 from the ponds with the net and filling cans with them in almost drained 

 condition, adding table salt to prevent their rapid decomposition They 

 are then parboiled, strained and evaporated to dryness at low temperature 

 or by spreading in the sun in hot weather. This food contains all the 

 essentials of the pond animalculas, and will keep almost indefinitely, 

 further eliminating all danger of introducing enemies into the rearing tanks. 

 In its dried state it is used in the best prepared fish foods. 



Propagating Natural Food. The artificial propagation of natural 

 food has received considerable attention from the culturists of food fishes. 

 These consist of the minute fresh water fauna together with the larvae of 

 mosquitoes, gnats, mayflies, dayflies, smaller bugs and beetles. Ditches 

 in the vicinity of the fish propagating basins, for the cultivation of natural 

 food, are prepared with a layer of cow manure in which water plants, in- 

 cluding potomogeton, anacharis, cress and confervae are grown, and partly 

 filled with brushwood, bricks, stones, etc.; in which the animalculae may 

 secrete themselves; and from which they are let into the ponds with the 

 water supply. 



Feeding in the Aquarium. To assure success with the aquarium, 

 it must not only be in natural balance but the food should be either the 

 natural small pond life, or simulate that of nature, and prepared to furnish 

 to the living inmates the proper constituents in correct chemical propor- 

 tion and easily digestible form. ' Natural live food should be fed when it 

 can be procured, and which may consist not only of the tiny water ento- 

 mostraca, but of the larvae and pupae of mosquitoes, fly maggots, particles 



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