Ammonia toxicity


Ammonia elevated >0.02ppm un-ionised
The un-ionised ammonia causes toxicity. Calculate this from Total Ammonia with RSFP Ammonia Test and chart therein.
Gills bleeding
Breathing at surface
Fish stays at surface usually at an inclined angle and breathes or sucks air.
Distal part of fins lose colour
Upper parts of fins lose their natural colour.
Fish jump out of water
Fish periodically leap above water surface trying to get air.
Abnormal swimming - streaks
Fish swims in short bursts, then stops.
Fins frayed or ragged
Fins look as if they are rotting away, giving eroded appearance.
Mouth and opercula wide open
The mouth and gill covers are extended open, as fish tries to get enough air.
Skin excessive sliminess
Skin shows mucous and slime far in excess of normal.
Hanging at surface
Fish stays at water surface all the time.
Listless and lethargic
Fish moves very lazily in water, much less than normal, lacks interest.


Excess ammonia level, usually more than 0.4ppm TOTAL ammonia. Toxic level depends mainly on pH, less on temperature. Cause can be dead fish in tank, malfunctioning biofilter, excess food, etc. While ammonia toxicity can be observed in both fresh and salt water, it is much more lethal in salt water as the higher pH level means the NH3 level which is major cause of death rises as a percentage of the total ammonia. The NH3 percentage is a gas which can penetrate the gill membranes of fish, causing rapid mortalities. 


Find reason for excess level and correct. Fish will improve very fast on lowering ammonia levels.


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