COMPARATIVE EVALUATION OF ORGANIC AND INORGANIC COAGULANTS MITIGATION OF WATER TURBIDITY IN FOR CLAY BASED EARTHEN FISH POND

Abstract

Comparative evaluation of inorganic and organic coagulants in mitigating turbidity of water caused by clay was studied; 25litres of turbid water with clay particles were collected in plastic bowls and physicochemical parameters were determined. Each inorganic coagulant was placed separately into different bowls at dosages of 0.2, 0.4, 0.6, 0.8 and 1.0g/25l while organic coagulants at the rates of 25, 50, 75, 100 and 125g/25l. The contents were stirred vigorously for 1-2 minutes at intervals of 5 minutes for 30 minutes and physicochemical parameters were determined after 30 minutes while scoring for increasing clarity (1-5) by three assessors using Likert scale. Five Juvenile Clarias gariepinus were placed in the bowls of different concentration for every coagulant and activities of the fish were observed. The experiments were replicated three times. The data obtained were analysed using descriptive statistics and all the coagulants revealed that the mean values of pH, conductivity and total dissolved solid (TDS) increased with increased rates of application generally. Temperature (290C) remains constant in all the treatments. The range values of pH (6.4-7.5), TDS (141-321) and conductivity (220.31-501.56µS). Fish in treated water were active at dosages of Alum (0.2 – 0.8g/25l); Gypsum (0.2, 0.6 and 0.8g/25l); Ash of rice straws (25 and 100g/25l) and were very active for bale of hay of rice straws (100 and 125g/25l). Organic coagulants, readily available as wastes, can replace the inorganic ones by applying 100g/25l of Bale of hay of rice straws. Further research is recommended on dosages of Ash lower than 25g/25l.