Nitrite is a waste product produced by bacteria in the biological filter as it breaks down ammonia. Nitrite is extremely harmful to fish and can result in severe fish loss. Nitrite levels should be kept at 0ppm. In the spring, the water starts to warm up and nitrite can build up as the fish begin to eat and the type of bacteria that converts ammonia to nitrate is performing only at halfspeed. The deadly Nitrite passed through the gills and oxidizes the iron in the fish blood, preventing it from carrying oxygen and causing the fish to be in demand for oxygen. Salting the water will help the fish resist the effects of nitrite and avoid the low oxygen levels in the body. Salting at a .5% can correct nitrite spiking problems but you cannot have plants at this salt level!
Now, remember the Beneficial Bacteria you added?. This same Beneficial Bacteria that you added to “seed” your pond to introduce Nitrosomonas into the Ecosystem also contains another strain of “good bacteria” called Nitrobacter, which reduces the Nitrite into Nitrate. Again, it takes time for these “beneficial nitrogen reducing bacteria” to develop. Under normal conditions, it takes up to six weeks for the Nitrobacter to proliferate to number sufficient to reduce all Nitrite in the environment. This Nitrobacter Bacteria converts the toxic nitrite into relatively harmless Nitrate (an excellent plant food).
NITRATE is the byproduct of nitrifying bacteria in the biological filter breaking down ammonia and nitrite. It is used by plants and algae as a food source. High levels can lead to excessive algae growth and damage to pond plants. Keep below 200 ppm Algae and plants use the Nitrate. An excellent plant food There are also strains on Denitrifying bacteria in the Beneficial Bacteria that you put into your pond. The denitrification cycle is the biological reduction of Nitrate to harmless Nitrogen Gas which exits the pond into the atmosphere. This process is one that does not occur right in the pond water but works in your Biofiler or filtration unit.
This completes the cycle, allowing you to add additional fish and commence regular and periodic partial water changes. If you perform water changes, make sure that you add a chlorine/chloramine remover since chlorine not only a detriment to the fish but will equally detriment the “good” bacteria that have been seeded in the Biological filtration unit.
Fish waste/food/excretions – Ammonia – Nitrosomonas – Nitrite – Nitrobacter – Nitrate – plant food & algae – Fish eat the plants (roots, stems and foliage in my pond!) – fish waste/excess fish food/excretions – ammonia – the cycle goes on
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