Transcript here - Fair City Aquarist Society

Graham Ramsay
Fair City Aquarist Society
Understanding the nitrification process is the
single most important step to success in keeping
fish
Nitrification is the conversion of toxic fish waste
(Ammonia) into Nitrite then Nitrate
An aquarium is a “Closed System” – fish have to
live in their own waste material – this is mainly
Ammonia
Ammonia is a product of fish respiration and is
excreted via the gills
Ammonia is highly toxic to fish – there is no safe
level
The higher the temperature and pH the more
toxic it is
Gill irritation – scratching and gasping at the
surface
Skin, eyes and gill damage
Lethargy, loss of appetite
Clamped gills, lying on the bottom
Death
Bacteria consume the ammonia and excrete
Nitrite
Nitrite is toxic to fish – there is no safe level
Ulcers, fin rot
Gill irritation and lethargy
Brown gills and respiratory distress
Death
Bacteria consume Nitrite and excrete Nitrate
Nitrate is safe at low levels
High levels encourage algae and weaken fish
Very high levels are toxic to fish
Nitrate levels are kept in check by regular water
changes
Bacteria live on surfaces – gravel, plants, filters
Require food and oxygen
Keep filters clear – rinse in tank water
New tanks won’t have enough bacteria
Fish die when added to a new tank
Fish excrete Ammonia and levels build up
Start with only one or two fish
Feed very little
Wait until bacteria build up
Consider starting your tank without fish
Requires a source of Ammonia
Levels need to be measured regularly
You can add fish when the process is finished
Start with a few then add slowly
Happens when no water is changed
Nitrate levels rise
pH falls
Water discoloured
Nitrifying bacteria die
Ammonia is present but not toxic
pH may crash
New fish added die quickly – shop blamed
Existing fish seem fine
Sudden water changes raise pH
Ammonia becomes toxic again
Regular water changes
Keep filters clean
Fish excrete toxic waste
Bacteria convert it to nitrate
Remove nitrate by doing water changes
New tanks don’t have bacteria
Start slowly – without fish if you can
Don’t forget your water changes!!!