Richard bray

Nitrification refers to transforming ammonia into nitrites, and then into nitrates, which is a plant-soluble form of nitrogen.
Mineralization refers to the process of transforming the rest of the fish waste into all the other nutrients that plants need to grow.
Oxygenation refers to adding and maintaining dissolved oxygen levels in the water so that the fish can breathe, and so the bacteria are able to continue transforming waste into nutrients.
All three of these processes are influenced by water temperature, air temperature, pH, mechanical filtration, biological filtration, water
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circulation, fish feed, fish species, plant species, light, and water quality.
The majority of the labor involved with maintaining an aquaponic system is testing, logging, and adjusting these factors. A large part of aquaponics is chemistry, and there is no such thing as a successful aquaponic system without a basic understanding of how plants absorb nutrients.
Nitrification
Nitrification is the most important chemical process in an aquaponic system.
Fish excrete ammonia from their gills, and this ammonia can quickly build up and become toxic if it's not removed from the water. Ammonia (NH3] is a gas, and is constructed with one nitrogen atom and three hydrogen atoms.
Nitrosomonas is the most common bacteria associated with transforming ammonia into nitrite. These bacteria oxidize the ammonia, which forms the equally-toxic, but necessary, chemical compound N02-.
The equation for this process looks like this:
NH3 (ammonia] + 02 (oxygen] = NO2 (nitrogen dioxide] + 3h+ (hydrogen ions] + 2e- (electrons]
In layman’s terms, bacteria mix ammonia and oxygen together to form nitrite. A byproduct of this process is hydrogen ions, which is what is
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measured during a pH test. So, the first step of nitrification will provide nitrite, and lower the pH of the water.
Nitrobacter is the most common bacteria associated with transforming nitrite into nitrate. These bacteria oxidize the nitrites, which form the plant-soluble, non-toxic chemical compound NO3-.
The equation for this process looks like this:
N02- (nitrogen dioxide) + H20 (water) = NO3 (nitrate) + 2H+ hydronium ions) + 2e- (electrons)
"This process produces a form of nitrogen, NO3, which plants can absorb. Hydronium ions are also produced, which will lower the pH of the water.
loth ammonia and nitrites are toxic to fish, so it's important for the unification process to clean the water thoroughly as it circulates through the filters and grow beds. The most important factor in this process is BSA, or biological surface area.