The Role of Nitrogen in Water Gardening | Ornamental Ponds is Very Complex One.. Some Forms are More Toxic.. Than Others

What rate does the nitrogen cycle play in Water Gardening and Ornamental Ponds?

The overall role of nitrogen in water gardening is a very complex one. Just about all forms of nitrogen can be polluting to streams and aquatic environments, although some forms of nitrogen compounds are more toxic to fish and other animals, some affect BOD/COD more than other forms, and some forms affect pH of the aquatic environment more than others.

Which are the form of nitrogen and the worst for water gardening?

That depends upon the situation. Waste entering a water gardening generally has a relatively high level of ammonia in it as compared to nitrogen in nitrate form. Ammonia is odorous, volatile and raise the pH of the total water. As oxidation of waste water proceeds in the water gardening, more of the nitrogen is ideally converted to nitrate form. This process is know as the NITRIFICATION process. The nitrate form is less toxic to aquatic life and does not contribute to COD in the treated waste. The problem of nitrogen contamination does not stop there however, since nitrate is a plant nutrient. Therefore attempts are made to remove nitrate nitrogen from water gardening as well.

How can nitrates be removed from water gardening ?

Biologically, nitrate (NO₃) may be stripped of their oxygen by certain types of bacteria. The bacteria, when they are restricted from access to oxygen, utilize nitrate instead of oxygen for respiratory purposes and biochemically pull away the oxygen component of the nitrate ion. The net results of this process of DENITIFICATION is nitrogen gas which bubbles back into the atmosphere and is non polluting.

Can bioremediation agents contribute microflora that can affect the fate of nitrogen in a system ?

Product such as those that contribute only Bacilli and Pseudomonas may help to denitrifynitrogenous waste once the form of nitrogen is in the nitrate (NO₃) form. They may help contribute to the natural microflora’s performance on  ammonia in a system, but these cultures cannot directly oxide ammonia to nitrate. Baxel's product contains a blend of microorganisms form the Nitrosonomonas and Nitrobacter genera that are known to oxidize ammonia to nitrate. This bioremediation product also contains selected strains of microbes that can denitrify, or convert nitrate to nitrogen gas, thus completing the cycle for effective removal of nitrogen from an aqueous system.

Technical people tell us that certain ammonia oxidizing bacteria are very difficult to grow and are even more difficult to count and reisolate.

This is true. Nitrosomonas and Nitrobacter species are typically very slow growing in even ideal environments. This is one reason that it is so critical to maintain a nitrifying bacteria presence in water gardening facilities. Once they are killed as by toxic shock, or washed out  of a system, they are difficult to reestablish. Nitrifiers are also very difficult to isolate from complex mixtures of microbes. This isolation can be accomplished only with specialized media and techniques. Even pure cultures of these bacteria are tough to count and enumerate with any degree of precision. However, isolations of ammonia-oxidizing bacteria can be accomplished using specialized media, component microbiological practice, and patience.

Do commercial bioremediation products for assisting nitrogen control guarantee positive results ?

NO. Bioremediation agents are intended to help a system work as efficiently as possible, given that all other desirable conditions are present. If, for example, there is insufficient dissolved oxygen in a system, or overwhelming biochemical oxygen demand, then it is highly unlikely that nitrogen (or conversion of ammonia to nitrates) will be accelerated. Unless some area of the system is oxygen limited, then it is unlikely that appreciable denitrification of the waste will occur. Sometimes specialized facilities, often referred to as tertiary treatment facilities, must be constructed in order to fully facilitate nitrogen removal from waste waters. Since nitrifiers and denitrifiers are sometimes difficult to isolate from nature, however, introducing sources in form of a bioremediation product may assist the system in becoming more efficient and reliable.