166 FISH CTJLTUEE 



feeding advanced fry and fingerlings, and no 

 more excellent nourishment can be recom- 

 mended. To prepare it for use the blood from a 

 slaughtered animal, while still warm, is run di- 

 rectly into a barrel and stirred vigorously until 

 it is smoothly thick. Blood allowed to thicken 

 without stirring is clotted, stringy, and unfit 

 for feeding purposes. 



Cleanliness Required. — Clean ponds are as 

 important factors towards success as the char- 

 acter and quantity of the food. Dead fish 

 should be removed at once. In every hatchery 

 there ought to be a standing rule that every 

 pond must be gone over the first thing each 

 morning, and any fish which may have died 

 during the previous 24 hours taken out. Filth 

 of any kind and certain forms of algae must 

 not be allowed to accumulate, and the ponds 

 therefore need to be cleaned at regular inter- 

 vals. It is as necessary for the health of the 

 fish that the ponds be kept clean, as it is for the 

 well being of a man that the house in which he 

 lives be kept free from filth ; in both cases dirt 

 breeds disease. 



Ponds with concrete, or building-tile sides 



