Evaluation on some nitrogen degrading bacteria for culture of glass ell

Abstract

Nitrogen (N) degrading bacterias are needed for the control of fish culture organic waste. The purpose of the study was to evaluate N- degrading bacterias on survival, growth performance, blood profil, and media water quality for glass eel culture. Twelve aquaria were used at rate of 20 fish/L water. Artemia sp and peleted diet were fed at satiation on test fish for 60 days of experimental period. Completely randomized design with 4 treatments and 3 replications were used. The treatments were different N- degrading bacterias, namely: A) no bacteria (control); B) Nitrobacter sp, C) Pseudomonas sp, and D) Bacillus sp. The parameters tested were survival rate, absolute growth and length, blood profil, and water quality. The results showed that Bacillus sp was the best bacteria for degrading nitrogen to produce the best values of survival rate (90.62±0.40%), total length (9.31±0.59 cm), body weight (1.04±0.17 g/fish), total erythrocytes (1.04×106-1.10×106 cells/mm³) and total leukocytes (7.61×106-8.85×106 cells/mm³). Nitrite, nitrate, ammonia concentrations in culture added bacterias were relatively stable and lower than those at control. It could be stated that adding Bacillus sp can improve survival, growth performance, and blood profil as well as uphold water quality in optimal range conditions.