How do filter bacteria work and why are they important?

In previously published articles about the nitrogen cycle and the most important part of it is the nitrification process We've seen that bacteria apparently play a crucial role in our biological filters. These extremely useful, hard-working people never complain, but they do impose some demands on working conditions.

What do bacteria do in the pond?

The bacteria in our biological filter convert highly toxic ammonia (and ammonium) via dangerous nitrite into virtually harmless nitrate. These bacteria are (chemo)autotrophic. This means they are able to extract energy from oxidizing (burning) inorganic substances (such as ammonia and nitrite) by converting them into substances that organisms can then use as nutrients. Nitrate, for example, is an important nutrient for plants and is also found in fertilizers and similar products. Autotrophic bacteria are, so to speak, the recyclers of our planet and thus fulfill an important function (just like green plants, which are photoautotrophic).

What are the ideal conditions for pond bacteria?

To do their job optimally, the filter bacteria have a few requirements. Don't worry. They're employed for free through tap water, work 24 hours a day, and don't protest monthly on the Malieveld. However, as a responsible employer, you are responsible for ensuring proper working conditions:

• Sufficient surface area for attachment in the form of substrate (caldnes, beads, mats, etc.) in your biological filter.
• Sufficient oxygen (minimum 7 milligrams per liter) in the water.
• Sufficient CO2 (for the development of the bacteria).
• Stability in the form of pH (between 7.0 and 9.0) KH (between 3 and 10 degrees DH)
• Temperature (in warmer water the bacteria work harder)
• Nutrients (in the form of ammonia)
• Dark (autotrophic bacteria do not like light)
• Sufficient flow, so that waste products from the pond are quickly transported to the filter.

How can I promote the growth of pond bacteria?

The number of nitrifying bacteria depends on the conditions you, as a pond manager, create. This bacterial population is normally adjusted to the food supply in the form of waste products excreted by the fish. The population needs time to adjust to changing conditions. Sudden changes, such as adding fish or using harmful medications, can cause a shortage of bacteria, leading to dangerously high ammonia and nitrite levels. Recovery and growth of a bacterial population simply takes time. Therefore, it's important to make changes as smooth as possible. This gives your workforce time to adapt to the changing conditions without leading to dangerous water parameters.

How often should I add bacteria to the pond?

When starting a new pond, during maintenance, or when adding fish, you can add some extra bacteria to your pond. Most bacteria don't survive the winter but will start growing again in the spring. To give them an extra boost, you can add some bacteria.

What are the best pond bacteria?

If you are looking for bacteria to solve a specific problem or want a complete package, you will soon come across the line of pond bacteria from the brand Secret .

Author: Joop van Tol (www.koitoday.nl)