I thought that I would do a write up on the nitrogen cycle for begginers or anyone who wants to know more about the nitrogen cycle:
The Nitrogen cycle
The nitrogen cycle is one of the most crucial parts of both large scale and small-scale aquaculture system water quality. Without the Nitrifying bacteria of the nitrogen cycle, the water would become too toxic to be inhabited by most forms of life, including fish. High levels of ammonia, or un-ionized ammonia, can cause decay of the gills and internal hemorrhaging. High nitrite levels can cause brown blood disease, and nitrates in a high concentration can cause algae blooms, and indirectly kill fish.
The two most notable and important types of bacteria in the nitrogen cycle are the genus Nitrosomonas, and the genus Nitrobacter. Bacteria in the genus Nitrosomonas convert ammonia into less dangerous nitrites. Although these nitrites are less dangerous than ammonia, they are still dangerous to livestock. Thats when the genus Nitrobacter is needed. Bacteria from this genus convert nitrites to less harmful nitrates. Nitrates are rarely harmful to fish, and usually only harm the crop indirectly by causing an algae bloom. There are however, many forms of anaerobic bacteria that use nitrogen gas instead of oxygen gas for respiration, thus splitting the nitrate (NO2) molecule into beneficial oxygen gas, and harmless nitrogen gas.
Ammonia, which is also referred to as NH3, is the most toxic component of the nitrogen cycle. Ammonia is acutely toxic at concentrations as low as .6ppm, and can kill fish within days. Exposure to ammonia causes a fishs gills to burn and hemorrhage, which inhibits the gills ability to removed dissolved oxygen from water. This causes oxygen depletion within the fishes bloodstream, which can and will cause brain damage and internal hemorrhaging with prolonged exposure. If the fish is not removed from water containing even low levels of ammonia (below .1ppm), growth can be stunted, and the fish may never make it to harvesting size.
Nitrites, although not as toxic as ammonia, can still harm or kill the crop. In acute concentrations (higher than 1ppm) nitrites can cause the hemoglobin in a fishs red blood cells, which contain iron, to oxidize. Once the hemoglobin in a fishs blood oxidizes, the blood cells can no longer carry oxygen, which gives the blood a brown color. This disease is know as brown blood disease, and can be observed externally by symptoms such as brown gills, brown lesions, and fish showing signs of oxygen depletion, which include loss of appetite and piping.
Nitrates are relatively harmless to fish, but in high concentrations, they can indirectly harm fish. They do this by causing an algae bloom. Since nitrates are a factor in accelerated algal growth, phytoplankton will begin to grow at an accelerated rate. When phytoplankton blooms, it will cause turbidity, or a decrease in light penetration due to small particles in the water. This turbidity reduces light penetration at the bottom of a culture vessel, which reduces the amount of photosynthesis at the bottom, and therefore the amount of dissolved oxygen. This decrease in dissolved oxygen will in turn cause oxygen depletion, some symptoms of this include; piping, fish gathering at incoming water, loss of fish appetite, and loss of fish vigor, or activity.
The nitrogen cycle is the largest contributor to water quality, and components of the nitrogen cycle must be closely monitored. The number one result of high nitrates, nitrites, or ammonia levels is oxygen depletion, which can sometimes be solved by mechanically aerating the water, or oxygenating the water by directly injecting oxygen or outside air. Another way to avoid High levels of NH3 (ammonia), NO3 (nitrite), or NO2 (nitrate) is to avoid overfeeding, and collecting and removing any excess waste or other organic mater, which can rot, causing ammonia to build up.
Brown blood disease:
Ammonia Poisoning:
The Nitrogen cycle
The nitrogen cycle is one of the most crucial parts of both large scale and small-scale aquaculture system water quality. Without the Nitrifying bacteria of the nitrogen cycle, the water would become too toxic to be inhabited by most forms of life, including fish. High levels of ammonia, or un-ionized ammonia, can cause decay of the gills and internal hemorrhaging. High nitrite levels can cause brown blood disease, and nitrates in a high concentration can cause algae blooms, and indirectly kill fish.
The two most notable and important types of bacteria in the nitrogen cycle are the genus Nitrosomonas, and the genus Nitrobacter. Bacteria in the genus Nitrosomonas convert ammonia into less dangerous nitrites. Although these nitrites are less dangerous than ammonia, they are still dangerous to livestock. Thats when the genus Nitrobacter is needed. Bacteria from this genus convert nitrites to less harmful nitrates. Nitrates are rarely harmful to fish, and usually only harm the crop indirectly by causing an algae bloom. There are however, many forms of anaerobic bacteria that use nitrogen gas instead of oxygen gas for respiration, thus splitting the nitrate (NO2) molecule into beneficial oxygen gas, and harmless nitrogen gas.
Ammonia, which is also referred to as NH3, is the most toxic component of the nitrogen cycle. Ammonia is acutely toxic at concentrations as low as .6ppm, and can kill fish within days. Exposure to ammonia causes a fishs gills to burn and hemorrhage, which inhibits the gills ability to removed dissolved oxygen from water. This causes oxygen depletion within the fishes bloodstream, which can and will cause brain damage and internal hemorrhaging with prolonged exposure. If the fish is not removed from water containing even low levels of ammonia (below .1ppm), growth can be stunted, and the fish may never make it to harvesting size.
Nitrites, although not as toxic as ammonia, can still harm or kill the crop. In acute concentrations (higher than 1ppm) nitrites can cause the hemoglobin in a fishs red blood cells, which contain iron, to oxidize. Once the hemoglobin in a fishs blood oxidizes, the blood cells can no longer carry oxygen, which gives the blood a brown color. This disease is know as brown blood disease, and can be observed externally by symptoms such as brown gills, brown lesions, and fish showing signs of oxygen depletion, which include loss of appetite and piping.
Nitrates are relatively harmless to fish, but in high concentrations, they can indirectly harm fish. They do this by causing an algae bloom. Since nitrates are a factor in accelerated algal growth, phytoplankton will begin to grow at an accelerated rate. When phytoplankton blooms, it will cause turbidity, or a decrease in light penetration due to small particles in the water. This turbidity reduces light penetration at the bottom of a culture vessel, which reduces the amount of photosynthesis at the bottom, and therefore the amount of dissolved oxygen. This decrease in dissolved oxygen will in turn cause oxygen depletion, some symptoms of this include; piping, fish gathering at incoming water, loss of fish appetite, and loss of fish vigor, or activity.
The nitrogen cycle is the largest contributor to water quality, and components of the nitrogen cycle must be closely monitored. The number one result of high nitrates, nitrites, or ammonia levels is oxygen depletion, which can sometimes be solved by mechanically aerating the water, or oxygenating the water by directly injecting oxygen or outside air. Another way to avoid High levels of NH3 (ammonia), NO3 (nitrite), or NO2 (nitrate) is to avoid overfeeding, and collecting and removing any excess waste or other organic mater, which can rot, causing ammonia to build up.
Brown blood disease:
Ammonia Poisoning:
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