Published in Scientific Papers. Series "Management, Economic Engineering in Agriculture and rural development", Vol. 23 ISSUE 1
Written by Tarek FOUDA, Abd-Elrahman ELRAYES, Abd-Elhameed ELHANAFY

This study discussed the effect of application optimum operational conditions for fine bubbles aeration of 0.554 m³.h^-1 air flow rate, tube depths from water surface of 0.7 m, tube inner diameter of 11 mm, circular design shape at aquaculture greenhouse for rearing Nile Tilapia and compared with traditional water change system in three replicates for every treatment. Water change ratios were 10 and 30% for fine bubbles and traditional water change method, respectively. The experiment period were 8 weeks until reach commercial size. The water quality indicators were: Dissolved oxygen (DO), Total ammonia nitrogen (TAN), Temperature, Total dissolved solids (TDS), pH. Also, the Fish growth indicators were: Weight gain, Feed conversion ratio (FCR) and survival rate, Specific growth rate (SGR). The best FCR value was 1.181 and obtained at the seventh week for fine bubbles aeration. The maximum SGR value was 1.96 which obtained at the seventh week for fine bubbles aeration, while the minimum value was 0.86 obtained at the fifth week for water change method. The maximum mean value for dissolved oxygen was 91% of saturation obtained at fine bubbles aeration method. Also, the minimum mean value for total ammonia nitrogen was 0.32 mg/l obtained at fine bubbles aeration method. The minimum and maximum mean values for total dissolved solids (TDS) in fine bubbles treatment were 1.610 and 1.7 mg/l, respectively.

[Read full article] [Citation]