Bacteria and Cold Water

Posted in Pond Bacteria, Ponding 101, Water Quality, Winterization at 6:51 pm by Administrator

There are live (vegetative) beneficial bacteria in our pond, and there are spore-based (beneficial) bacteria.  The spore-based bacterium does not have the adaptability and competitive edge which our vegetative strains do, but at the same time, they will work better in the colder temperatures.  All bacteria slows down in winter if the water temperatures are lower than 45-50F.  But the vegetative, which is super-active during the summer months, when the organic loading is at its highest, are the first to slow down and “sleep” when the temperature drops.  Being alive, they have a metabolism which, although they do not die, will slow down considerably.

For best results, add your live (odorous liquid) bacteria once the water temperatures have gotten back into the more hospitable ranges.


Q. How do I know if I have bacteria in there?  How do I know it is working in my pond?


A. The first signs of bacteria working for you will be to lower ammonia nitrogen levels in spring, converting it to nitrite and then to nitrate.  So, if you are doing water testing, you will see the levels fluctuating as the process begins to percolate.

Then, you can see without a water test to know the nitrates are forming by biological/chemical conversion by the perennial algae bloom and emergence of pond plants.  If the bacteria were not functioning properly, your pond would not “come to life” each spring.


Q. So, if I get an algae bloom and have no measurable ammonia or nitrites, then why do I need to add more bacteria??


A. Bacteria take in nutrients until they are so fat they split in two.  Then, there are two (or more) bacterium where there initially was one.  This can occur in as little as a few hours in the pond.  The warmer the water, the more speedily they will divide (multiply).  Ah, but, the catch is that after about 4-5 divisions, they lose some of their original potency.  So, by adding a larger initial dosage, followed by smaller ones on a regular basis, you will keep a sufficient quantity to maintain the integrity of your pond system.


Q. What about the powdered bacteria?  Is it as good as the smelly stuff?


A.  It has pros and cons, but overall, it can never do what the live bacteria will.  It will contain a limited number of strains, producing limited types of enzymes, so the job may remain half-finished.  Whereas, by using the vegetative (live, liquid) bacteria blends, you will assure whatever your fish, food, and pond surroundings throw at it this year will be oxidized (broken down).


Q.  Is there a limit to how much the beneficial bacteria can do for my pond?


A.  Yes.  Your pond is part of a complete system, containing filtration, circulation, and maintenance.  The amount of fish, the volume of food supplied, and even weather conditions, if in excess, will overwhelm the pond to the point where the bacteria alone cannot clean it up.  Your responsibility is to stock carefully, feed prudently, maintain the filter and skimmer, and do water testing.  You need to do water changes to lower the pollution levels if you notice too high organic loading.  This will be obvious by the look and smell of the pond, or the health of your fish.  Bacteria will grow at the rate of the “food” supply, but it can become overloaded without proper maintenance.

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