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ammonia and nitrite final.pptx

  1.  Ammonia in the pond water is a by-product of metabolism by animals and bacterial Decomposition of organic matter such as wasted food, faeces, dead planktons etc.  In water, ammonia nitrogen occurs in two Forms, un-ionized ammonia and ammonium ion (NH4).  Un-ionized ammonia is determined By total ammonia concentration, ph, and water temperature and to a lesser extent on salinity.  It is considered more toxic form of ammonia due to its ability to diffuse readily across cell Membrane, hence should be less than 0.1 ppm.
  2.  A given concentration of un-ionized ammonia Is more toxic when dissolved oxygen concentrations are low. 0.02-0.05 mg/litre Safe concentration 0.05-0.4 mg/litre Sub lethal effect 0.4-2.5 mg/litre Lethal effect
  3.  Take 5 ml of water sample  Add 1ml of trisodium nitrate  Add 1ml of phenol nitro phosphate  Add 1ml of sodium hyphochlorite  Cover it with aluminium soil  Keep at dark room for 2 hrs  Observe it under spectro photometer at 630 nm
  4. 0 0.02 0.04 0.06 0.08 0.1 0.12 10:00 AM 12:00 PM 2:00 PM 4:00 PM pond no 5 pond 7 pond 8 pond 11 wet lab reservoir
  5.  Maintaining sufficient level of Dissolved oxygen  periodic partial removal of algal blooms  water exchange and addition of Liming agents such as hydrated lime or quick lime  Add zeolite to absorb obnoxious gas
  6.  Nitrite is an intermediate product in biological oxidation of ammonia to nitrate, a process called nitrification  Nitrite is highly toxic to fish as it oxidizes hemoglobin to form methemoglobin, which is incapable of transporting oxygen.  Nitrite toxicity is affected by water pH and the presence of chloride and calcium ions.  Toxicity increases with increasing pH and decreases with increasing calcium and chloride concentrations.
  7.  Optimum level of nitrite is less than 0.25 mg/L.  Optimum level can be maintained by effective removal of organic waste, adequate aeration, correct application of fertilizer & feed and use of biofertilizer to accelerate nitrification.
  8.  Take 50 ml of water sample  Add 0.5 ml of sulphuramide solution  Then 0.5 ml of diamine solution  Obeserve the OD value at 543 nm
  9. 0 0.02 0.04 0.06 0.08 0.1 0.12 10:00 AM 12:00 PM 2:00 PM 4:00 PM pond no 5 pond 7 pond 8 pond 11 wet lab reservoir
  10.  Correct stocking,feeding and fertilization practices should be maintained  Pond should kept well oxygenated  Biofilteration should be done through special filters by conversion of nitrite to harmless nitrate occurs