Every healthy pond, lake and dam relies on a thriving community of beneficial bacteria. These aerobic (oxygen-loving) organisms form the foundation of a stable, self-sustaining aquatic ecosystem.
We call aerobic bacteria “good” bacteria because they do good things. When their populations thrive, water becomes clear, odour-free, and low in sludge and nutrients.
Low levels of nutrients in water means algae and weeds struggle to grow—they simply don’t have enough food.
This makes water management really quite simple: increase populations of “good” bacteria and the entire aquatic ecosystem comes alive. They are the key to creating and maintaining a healthy waterbody, long-term.
What Are “Good” (Aerobic) Bacteria?
The term aerobic bacteria refers to microorganisms that live in well-oxygenated environments. They are nature’s most efficient cleanup crew, breaking down organic waste such as decaying plants, fish waste, uneaten feed, dead insects, and other natural debris before it becomes sludge; fertiliser for algae and weeds.
These bacteria feed on nutrients like nitrogen and phosphorus, converting them into harmless compounds and gases that leave the system naturally. In doing so, they prevent nutrient overload—the main driver of poor water quality.
A high population of aerobic bacteria means the water is rich in oxygen, biologically active, and capable of self-regulation. It’s the most reliable indicator of a healthy ecosystem.
Why a High Population of “Good” Bacteria is Important
When beneficial bacteria populations are strong:
– Water stays clearer and cleaner, as organics are broken down before they accumulate.
– Nutrients are recycled efficiently, reducing the conditions that allow algae and weeds to thrive.
– Odours disappear, because aerobic bacteria produce clean by-products like carbon dioxide and water—not hydrogen sulphide or methane.
– Diversity increases, supporting a wide range of fish, aquatic plants, and micro and macroinvertebrates.
In short, a high population of aerobic bacteria leads to a balanced, resilient aquatic system—one that resists algal blooms and can recover quickly from stressful events like heavy rain or extreme temperature changes.
What Are “Bad” (Anaerobic) Bacteria?
By contrast, anaerobic bacteria thrive in oxygen-poor or stagnant environments. They dominate waterbodies that are poorly aerated and mixed. We call these guys the “bad” bacteria, not because we judge the little fellas, but because they lead to bad things.
They still break down organic matter—but very slowly and inefficiently. It often means the sludge is piling up faster than they can digest it. So, more and more nutrients enter the waterbody, fueling algal blooms and invasive weed outbreaks.
Worse, their by-products are toxic gases like hydrogen sulphide (the rotten egg smell) and methane.
A high population of anaerobic bacteria is a red flag for poor water health. It signals low oxygen levels, excess sludge, and often coincides with fish kills, surface scum, and foul odours.
Oxygen = ⬆ “Good” Bacteria, and ⬇ “Bad” Bacteria
The natural antidote to “bad” anaerobic bacteria is oxygen. When water is well-oxygenated—through aeration, water movement, and natural gas exchange—conditions shift in favour of “good” aerobic bacteria.
Once these “good” bacteria return in force, they outcompete the “bad” anaerobic microbes, restoring balance and eliminating the root causes of odour and poor water clarity. “Good” bacteria consume sludge at an outstanding rate when their populations are booming. Less sludge = less nutrients = less algae and weeds.
An aerator is the best way to increase oxygen in water. View our range of aerators.
The Hidden Danger of Chemical Overuse
Chemical algaecides, herbicides, and disinfectants can deliver quick results, but it’s important to understand they come at a biological cost. These chemicals don’t discriminate; they kill both the pest—the algae or weeds—but also “good” bacteria that keep water balanced.
When “good” bacteria populations crash:
- The dead organic matter left behind becomes fertiliser for the next generation of algae and weeds.
- The ecosystem becomes weaker and less capable of managing itself.
- Algae and weeds return sooner.
- Resistant strains of algae and weeds emerge, growing faster and spreading more aggressively.
Repetitive use of chemicals leads to a sicker and sicker waterbody; one that requires increasingly frequent interventions.
Biostim: Supporting the “Good” Bacteria Naturally
This is where Biostim comes in: you don’t need to rely on chemicals when you can rely on your waterbody taking care of itself.
Biostim is a 100% natural biological water treatment designed to boost and sustain populations of “good” bacteria in ponds, dams and lakes.
Made from a blend of natural enzymes, nutrients, and microbial stimulants, Biostim provides everything the “good” aerobic bacteria need to multiply and perform efficiently. It accelerates the natural decomposition process, reduces nutrient loads, and restores biological balance without harming fish, plants, or wildlife.
Biostim works in harmony with aeration systems—oxygenating the water while supplying the “food” beneficial bacteria need to thrive. Over time, this leads to clearer water, reduced odour, and long-term ecological stability.
Regular use of Biostim ensures the “good” bacteria in your water stay in control, creating a waterbody that cleans and balances itself naturally—just like any natural healthy lake or river.
1 + 1 = 3
When talking about aeration and Biostim, we say 1 + 1 = 3. They provide exponential results when paired together. You could just aerate, and you would help the health of your water, or you could just apply Biostim, and do the same, but when used together you can produce an extremely healthy waterbody. One you feel proud to have on your land.
Ready to Create Your Perfect Waterbody?
Contact us—we offer FREE expert advice. We can take a look at your waterbody on Google Maps and provide you with a FREE customised water treatment plan, no obligation. Alternatively, you can shop Biostim or look at our range of aerators.