AIR AND WATER TEMPERATURE OBSERVATIONS IN "PLASTIC TUNNEL" GREEN-HOUSE IN "TILAPIA-DO-NILO", OREOCHROMIS NILOTICUS, CULTURE

Abstract

The aim of this study was to follow during one year the performance of a simple green-house model "Plastic Tunnel" designed originaly for olericulture, targetting the winter production of the tropical fish Nile tilapia. The green-house of 240 m² (24 x 10 m) is located in a subtropical area and in the east-west direction. It has five cilindrical concrete tanks with the capacity of 8,000 liters each one. The support structure was made of eucalyptus rough wood and iron bars of one inch and covered by a plastic film 200 micrometers thick. Doors were placed at both sides in order to alIow ventilation inside the green-house. External and internal air temperatures, as weIl as that of the water of the five tanks were measured in the morning, at 8:00 to 9:00, and in the afternoon, at 16:00 to 17:00. Results of this study indicate advantages of the system growing and breeding tilapias year round.