Are we bringing knives to a biological gunfight?

The expression "Bringing knives to a gunfight." implies that what we're using in a battle simply isn't enough. Something like that is happening on NZ farms. When it comes to fighting POND CRUST, the "knives" we're bringing are the machines that are designed to break and stir and separate the solids. The machines are good - excellent examples of clever engineering. The problem is, they're design to deal only with the symptoms of the problem.
But the actual cause of pond crust is biological - micro-organisms that use effluent fibre to form the surface crust. For the farmer, negating these Anaerobic Bacteria is the real fight. The question is, how to you beat them?

ANSWER: Biologically.

How do Slurry Bugs win the fight?

  • Anaerobic bacteria love the dark and hate oxygen. They own the pond.
  • To create preferable conditions, these bugs separate effluent fibres and send them to the surface. These fibres form the crust.
  • Only a biological approach can beat these anaerobic bacteria
  • Slurry Bugs are aerobic bacteria. They love light and oxygen.
  • When introduced into the pond, Slurry bugs rise to surface and begin digesting the solid matter to let in the light and Oxygen.
  • Doubling in number every 20 minutes, Slurry Bugs begin transforming the pond from an anaerobic state to aerobic state.
  • After 5-6 weeks, the effluent crust is significantly reduced.
  • Also, the odour has virtually gone. The smell occurs when nitrogen vaporises – an effect caused by anaerobic bacteria.
  • Slurry Bugs have also cause the effluent nutrients to be retained in higher organic concentration. These nutrients are more readily available to plants.
  • Effluent is now easily pumped through irrigation nozzles.
  • Once the pond has reached an optimal aerobic state, the task is to maintain the bug balance = keeping the Slurry Bugs in charge!

Some farmers use MACHINES to deal with pond crust. Does that work?

  1. FACT: Effluent machinery does work. BUT, they only deal with the physical aspects of the effluent - namely the crust on the top and the sludge on the bottom. But the crust and sludge are only the visible physical symptoms of the real biological problem. What causes pond crusting and bottom sludge and pond odour and nutrient leeching in the soil and loss of usable nutrients are Anaerobic Bacteria. Expensive machines have no effect on these micro-organisms.
  2. FACT: As you can see in the diagram below, an effective machine-based system has more elements to the effluent management process. That means a lot more money spent (a) buying the equipment, (b) running the equipment, and (c) maintaining the equipment.
  3. FACT: Effluent machines do not stop the negative effects of the Anaerobic Bacteria - nutrient loss + odour + soil leaching and run-off.

Machine-based Process

Slurry Bugs Process

If these bugs multiply every 20 minutes, why do I have to put more in?

Fair question. Remember that the battle against pond crust is a biological fight: It is Good Bugs vs. Bad Bugs. Always. So here's the scenario: after using Slurry Bugs, your pond becomes clean and liquefied. That means that your Slurry Bugs are dominating and that the pond is in an aerobic state, which is good.


At some point you'll pump some of that nutrient-rich effluent onto your pasture. At the same time, new, raw effluent will enter the pond and that effluent is dominated by the bad bugs - the Anaerobic Bacteria. If left unchecked, the entry of these bad bacteria will tip the condition of the pond back to an anaerobic state = where the bad guys outnumber the good guys. If that occurs, the crust will return.

To keep your pond in good aerobic state, you simply keep the level of Slurry Bugs higher than the bad bacteria.
Slurry Bugs are naturally soil-born aerobic bacteria. These good bacteria are always part of the soil and they perform the following functions:

Are Slurry Bugs good for the soil?

  1. Slurry Bugs convert nutrients (Nitrogen + Phosphorus + Potassium) into organic forms that can be efficiently absorbed and used by plants, as the plants need them.
  2. Because the grass is able to receive the treated effluent nutrients, far less nutrient is lost into the surrounding environments in the form of leaching and run-off and emissions.
  3. More palatable grass: The organic form of the nutrients allows the plants to uptake what they need, when they need it. The result is a sweeter pasture that cows enjoy eating.

What is the real cost of using Slurry Bugs?

One pot treats 450 cubic metres of effluent. An easier rule of thumb is this: 3 pots per/100 cows for the entire year. If you have 500 cows, 15 pots of Slurry Bugs will keep your pond aerobic over a 12 month period. Another factor to considers is the state of your crust. The thicker your pond crust, the more there is for the Slurry Bugs to eat through. A badly affected pond may need an initial double hit to give the Slurry Bugs the fighting numbers they need.

The best approach is to talk to the Slurry Bugs people about your specific situation. They'll then give you an accurate costing.

Do I have to buy a YEAR'S WORTH all at once?

No, you don't need to buy a year's worth of SLURRY BUGS all at once. In fact, we'd prefer that you get your SLURRY BUGS on a monthly basis. This will allow us to monitor your progress and help you set up properly.
YES. SLURRY BUGS will eat through thick crust, but it may take a little longer than for a typical pond. The key to remember is this: BAD BACTERIA have made

Will these bugs still work if my crust is really thick?

the crust. The fact that your pond has a thick crust means that the pond is completely dominated by these bacteria.
To negate their effect, an extra dose of SLURRY BUGS will be needed at the start of the treatment. The reason for this is to allow to GOOD GUYS to establish their numbers. You may not see any apparent action on their part, but the SLURRY BUGS will be working night and day eating the crust from the bottom up. As their work progresses, you'll begin to notice changes to the pond's surface as the crust thins - liquid begins to seep through. With the correct ongoing treatment, the effluent will be liquefied.

Why does the crust keep coming back?

BIOLOGY. Anaerobic Bacteria are the cause pf pond crust. They make the crust by separating the fibres in the effluent and sending these fibres to the pond surface. These BAD BUGS come into your pond via the effluent.

That means every time you wash more effluent into the pond, you're increasing the number of bacteria that are dead keen to make a crust to block out the light and oxygen. That's why crust returns if the pond is left unmanaged.

And that's why you also need to keep the SLURRY BUG numbers up. Not only are BAD BUGS being added to your pond via new effluent, some of the GOOD BUGS (Slurry Bugs) in your pond are being lost every time you pump the good effluent out onto your pastures.

It's about keeping the GOOD GUYS vs. BAD GUYS numbers in balance.
If you stop using SLURRY BUGS, the ratio of crust MAKING bugs to crust EATING bugs quickly begins to favour

What happens if I STOP USING these bugs?

the bad guys. New CRUST MAKERS are being introduced to your pond with every influx of new effluent from the shed. And CRUST EATERS are being removed from your pond every time you pump the free-flowing effluent and spread it on to your pastures. That in-out trade off is unavoidable.

Consistently following a simple SLURRY BUGS plan will keep the GOOD BUGS in control of your pond.