Hmmm...Bacteria in a new pond. This is a topic I have grappeled with for a long time.
Since the pond is new, do you seed the pond with bacteria to start a culture? Alternatively, are these bacteria already there or likely to be there by the time you start to acquire a bio-load? Is your pond even ready to receive the bacteria?
Most of the bacteria we buy from our pond suppliers is naturally occurring bacteria in almost every water body and soil in the world. They are simply more concentrated and selected for a particular water treatment service. But, they have certain habitat requirements and one of these is a surface area to grow on.
Much like the bio-ball filters in an aquarium, the plants in your pond provide a surface area for these bacteria to grow. If you don't have plants in your pond, which it sounds like you don't, the surface area of "liveable" spaces for bacteria is significantly diminished and therefore, so is the effectiveness of the bacteria. In fact, in wastewater applications, engineers actually specify extended growth media to increase the surface area and therefore the rate of bacterial nutrient conversion.
It's my opinion (I have not found any literature on the topic so please share if you have) that until you have plants or other large areas of suitable bacteria habitat, it is pointless to add bacteria. You are simply not going to get a lot of bang for your buck. Furthermore, bacteria have other requirements in order to thrive. pH = 6-8.5, water temp > 55 F, DO > 2 PPM to name a few.
When buying bacteria, the salesman should ask similar questions as when buying an aeration system. What are your goals, water chemistry, inputs from watershed, etc... If your salesperson is not asking these types of questions, I fear that what BC said is true, he/she is just trying to sell some product.
BC, thanks for your input and not just passing off bacteria as "snake oil" as many do. I am a big advocate of bacteria, especially as a substitute for copper based algaecides...but only when the conditions are right.
