|ACCELOBAC®AG||A blend of bacteria and enzymes specially formulated for fresh water and brackish water aquaculture systems|
|ACCELOBAC®AGS||A blend of bacteria and enzymes formulated for use in higher salt concentration water aquaculture systems|
The worldwide seafood catch is declining because of over-fishing, pollution and expanding populations. Although aquaculture now represents only a small percent of the combined total, a leveling off of the supply of seafood together with the rising demand for fin fish and crustaceans means that aquaculture is the growth industry of the future. In this light, much emphasis has been placed on species selection, adaptation, feeding, rearing, harvesting, equipment or on other physical devices. But, little thought has been given to the accompanying aquatic environment, other than to change the water.
Mother Nature just can’t cope with the overload in the oceans, let alone the accumulation of uneaten feed, excreta, etc. in a confined aquatic environment. Where the water can be changed, it must be cleaned more often. Where the water can’t be changed, the confined aquatic environment deteriorates and so do profits.
Accumulation of uneaten feed and excreta create a sludge on the bottom and turbid water above. Digestion by indigenous microorganisms is slow and takes dissolved oxygen away from the crop. In addition, there is a build-up of ammonia, nitrites and other toxic or inhibitory products. Therefore, to improve the aquatic environment, there must be a reduction in accumulation of these substances. It is evident that these problems will not go away on their own. Also, it is evident that chemical and physical methods are costly and are only temporarily beneficial. To that end, what can be done that is both safe and cost effective?
The best point of attack is to reduce the accumulation of sludge. This is done by bio augmentation of the existing microorganisms through regular addition of biological active seed cultures such as ACCELOBAC® AG on a regular preventive maintenance schedule. Bio augmentation means helping Mother Nature do a better job microbiologically by supplementing the indigenous microflora. This is in contrast to the continued use of chemicals or increasing the frequency of water change, if, in fact, the water can be changed at all. Just like aspirin relieves some cold symptoms but does not cure the cold, chemical additives or water changes temporarily relieve the symptoms of the poor aquatic environment, but do not cure the problem.
Biologically Active Seed Cultures
Nature abounds with microbial cultures in the air, soil and water. These microflora exist because they have adapted and continue to adapt to changes in the environment. They have adapted because they can metabolize certain surrounding substances to obtain energy and nutrients. But, this does not mean they can handle an ever-increasing load.
An aquatic environment with few fish or crustaceans would probably clean itself over time. However, such a system would not feed many people or make a profit for the grower. Intensive aquaculture involves many fish or crustaceans and as many cycles as possible during a season. Accordingly, the aquatic environment is not able to clean itself under these circumstances, and limits have been reached in many places as to water changes and the benefits of more chemical additives.
Mortality and poor or abnormal growth are symptoms of a bad aquatic environment. If the aquatic environment is improved, the symptoms will disappear because the cause has been eliminated. How can this be done?
The answer is bio augmentation by regular additions of ACCELOBAC® AG which contains several strains of naturally-occurring microorganisms that have been isolated and trained to produce large amounts of digestive enzymes when introduced into an aquatic environment. This on the job training has been done to the extent that these biologically active seed cultures are strains which are 1000 times more active than those found in nature. By adding on a regular basis, these more efficient cultures establish themselves and maintain dominance over those less efficient already present.
Nitrification and Denitrification
Nitrification is a two-step process than involves two groups of microorganisms. The first step is oxidation of ammonia to nitrite. Nitrosomonas is the most common genus involved in this reaction. The most common genus involved in the second stage, oxidation of nitrite to nitrate, is Nitrobacter. Both of these genera are autotrophic and subject to dissolved oxygen (DO) and biological oxygen demand (BOD) limits. They are very fastidious in growth habits and attempts to culture them commercially have met with little success. Although ACCELOBAC® AG does not contain either, the product enhances the natural action by creating a more favorable environment, particularly by reducing the BOD. In addition, ammonia may be oxidized directly to nitrogen gas. In any event, the ammonia levels are reduced.
Several heterotrophic bacteria that aerobically oxidize organic matter can also reduce nitrites and nitrates and thus function as facultative denitrifiers. Among these are members or the genus Bacillus. ACCELOBAC® AG contains four species of this genus and the product functions as a facultative denitrifier as evidenced by university results which showed reductions in accumulation of nitrites and nitrates. Under low DO, the oxygen in nitrites and nitrates is utilized. However, as stated above reduction in nitrites and nitrates may be because of reduced ammonia accumulation.
The autotrophic denitrifiers do not function when the DO is above a critical level of 0.1 to 0.2 mg./L. A DO similar to this or slightly higher than that for the autotrophs will also inhibit activity of the facultative denitrifiers. If enough DO is available, this will be used in preference to the oxygen in nitrites and nitrates.
Presence of carbonaceous matter (sludge such as accumulated excreta, uneaten feed, etc.) will inhibit denitrification by the autotrophs. This does not influence the facultative microorganisms. ACCELOBAC® AG reduces sludge generation and accumulation as shown by its use in waste treatment plants and by university data. ACCELOBAC® AGS is a special formulation of ACCELOBAC® AG designed for use in saltwater aquaculture systems.
ACCELOBAC® AG does not contain Nitrosomonas or Nitrobacter. However, not only does this product function as a facultative denitrifier, it also creates a more favorable environment for the autotrophs by reducing the BOD. In addition, ACCELOBAC® AG may oxidize or otherwise utilize ammonia directly.Have a question?