Pond muck is the organic material that accumulates in the bottom of a pond. It can be physically removed with nets and vacuums, or you can try to degrade it using commercial bacterial products such as MuckOut, Macro-Zyme, Muck Pellets, MuckAway, Natural Clear, Mukk Busster, Muck Reducer, Muck Doctor, MuckBiotics and the product name I really like, ” Get The Muck Outta Here”. All of these products claim to reduce the amount of muck in the pond and some also claim to reduce the nutrient level.
Do commercial muck reducers work?
What Are Muck Reducing Products?
All these products contain bacteria. Bacteria play a major role in degrading organic matter in a compost pile, and they also naturally degrade the organic matter at the bottom of a pond.
The science is clear. Bacteria do degrade organic matter. But that does not mean adding some to a pond will speed up the degradation of muck in the pond. Claims like this, “MuckAway tablets sink below the water’s surface and dissolve, releasing hungry beneficial bacteria that instantly begin consuming and digesting the settled debris”, ignore the fact that the water and muck is already full of hungry bacteria.
Some of these products also include enzymes like lipase, protease, amylase, and cellulase. These are common enzymes produced by microbes to digest organic matter.
Scientific Evidence Provided By Manufacturers
I have looked at several of these products and none of the manufacturers provide scientific evidence that their product works.
I spoke with a product specialist at Airmaxeco, the manufacturer of MuckOut, Mukk Busster and Muck Away. He confirmed that they have not done any scientific studies on their product. He went on to say that “all of their evidence is anecdotal”.
I did find an independent study that looked at Mukk Busster, dated March 2022. They tested it on samples from three different lakes and found no change in organic matter even though the quantity of material they used was higher than recommended.
The same study also looked at bacteria populations. Each lake had a different type of bacteria dominating the water. Adding the muck reducer did not change the population. What this means is that the added bacteria did not become dominant. The product did not significantly change the bacterial population – it did not work!
This same report also referenced another non-peer reviewed study that looked at the addition of microbes along with aeration and found little to no effect (Slagle and Allen 2016).
Bacteria Decompose Pond Muck
What happens when bacteria decompose organic matter? Some of the carbon will be released as CO2, which will escape into the air. Some nitrogen and sulfur may also escape into the air as nitrous oxide, sulfur dioxide or hydrogen sulfide. All of the other nutrients will remain in the water since they are not turned into gases.
As bacteria consume the organic matter the population of bacteria grows. In effect the organic matter is converted into other organisms like bacteria and algae which are in turn consumed by larger organisms. Bacteria don’t live very long and when they die they become part of the organic muck at the bottom of the pond and the cycle continues.
There are two key points here. The amount of organic matter is slowly reduced because some of it is lost as CO2. At the same time the plant-available nutrient level in the pond will increase. Plants and algae are able to take these nutrients, along with CO2, and produce more plant matter.
This process happens all of the time, even when no commercial bacteria are added to the pond.
Do Pond Reducing Products Add Special Bacteria?
You might think that these commercial products consist of special bacteria that are not normally found in ponds, but that is not the case. What these products do is grow standard bacteria and provide them in a concentrated form.
A key question to ask is, do these products increase the bacterial population in the pond? The claim is that they do, but these companies provide no evidence that this actually happens. In fact the expert from MuckOut told me that they have never measured the bacterial population in a pond before and after adding their product. They don’t know if the population increases.
You might be thinking that this is obvious. If you add bacteria to a pond, the number must go up, but that is not true.
Bacteria multiply very quickly. Add a little food to a pond and the number of bacteria explodes to make use of the new food source. The population is very dynamic and changes quickly with a change in the environment (food, oxygen, temperature, etc). However, the population is always at capacity (i.e. maximum potential). Adding more bacteria to the pond does not increase the population because it is already at maximum capacity, given the current environmental conditions.
The exact same thig happens in soil. For details see, Buying Soil Probiotics (Microbes) – Are They Beneficial, Effective or Nonsense?
One of the manufacturers makes a point of saying, “bacteria counts double every 15 minutes or so”, and that is true provided there is a ready supply of food. If the food was in the pond for this to happen the natural bacteria in the pond would have already exploded in growth and you would not need to add more.
Note that the above mentioned study found no change in the bacterial population after Mukk Busster was added.
Is Muck Food For Bacteria?
Organic matter is food for bacteria, so why do the natural bacteria not clear out the muck more quickly?
This is the same process that takes place in a compost pile. You have probably heard of the fact that you need the right ratio of browns to greens in order for fast decomposition. It is actually not browns and greens – that is another myth you can read about here. It is about the carbon to nitrogen ratio (C/N ratio). If the C/N ratio is between 20 and 30, bacteria have a perfect food source and decomposition happens quickly.
Unfortunately, the organic matter at the bottom of the pond is mostly carbon – old leaves and dead plant material – and the C/N ratio is much higher than 30. It does not compost quickly because there is too much carbon relative to nitrogen. This also explains why a pile of leaves on the ground decomposes so slowly – a very high C/N ratio.
The C/N ratio does not change when you add extra bacteria into the water. Bottom line – muck is a poor food source for bacteria and that is why it accumulates.
Do Enzymes Remove Muck?
The enzymes that are added by some products will help break up organic matter. However, is the quantity added significant enough to make a difference?
Keep in mind that enzymes are also organic molecules and are subject to degradation. None of the manufacturers make any specific claim for them, except that they “do work”.
Do Muck Reducers Remove Muck?
I don’t see why they would work and unfortunately, the manufacturers have not done studies to show they work. That should tell you something.
Manufacturers suggest that these products work better when they are applied regularly and that adding bubble aeration helps a lot. The air circulation will help move muck from the bottom to upper levels of water and the extra oxygen will speed up decomposition. But aeration will do this on its own without added bacteria.
I suspect the added bacteria have a limited effect on muck. Show me some studies that say I am wrong.
Do Muck Reducers Remove Nutrients?
Even if the products speed up the decomposition of muck they can’t remove the non volatile nutrients which includes everything except nitrogen and sulfur. The nutrients stay in the pond and are available for plant use. Unless you have a lot of higher order plants, the excess nutrients will cause algae to grow.
MuckAway claims to reduce phosphorus levels in the pond by 90% but they do not provide a scientific study that shows this. Phosphorus is not volatile. The only way to remove it from a pond is to physically remove it, which makes this claim unbelievable.
Some product descriptions claim to remove nutrients along with the muck, but these are wrong. The expert at MuckOut/MuckAway even confirmed this with me. The nutrients stay in the pond.
Do Muck Reducers Work?
Given the number of products on the market and the fact that they have been around for some time, it is surprising that there is so little research on them. I suspect the scientific community has reservations about their effectiveness given what we know about the biology of bacteria. The manufacturers seem uninterested in funding research to prove their products work, which is not a good sign.
Muck reducers will not remove nutrients from ponds except possibly for nitrogen and sulfur. Therefore they have limited effect on algae growth.
Given the rapid rate at which bacteria multiply, the large amount of natural bacteria in ponds, the relatively small amount that is added by these products and the C/N ratio of the muck, it is unlikely that these products reduce pond muck.
Until manufacturers provide some independent scientific data to prove these products work, I would not buy them.
Reading your section on Carbon/Nitrogen imbalance, the logical conclusion would seem to be that you’d help the imbalance if you added nitrogen to the pond? No?
Adding nitrogen would change the balance – but in a negative way?
As a professional pond and lake expert, I would like to provide some insight about muck reducing bacteria. The case study linked in this article (about Mukk Busster) seems very unconvincing. Muck reducing bacteria are aerobic organisms which require oxygen to survive and thrive. In the noted case study, they used enclosed tubes that were incubated for 8 weeks straight which would sever any possible fresh oxygen supply to the water. The article also noted that open bins were used as a secondary study. These bins would also deplete of oxygen very quickly unless underwater aeration systems were used. However, as this equipment was not mentioned in the writing therefore assumed it was not present or being used. On another note, these micro-organisms need much more time than 8 weeks to establish and multiply enough to notice muck reduction at our much larger scale. Most results that I have personally been a part of are achieved no faster than 90 days. In conclusion, to achieve the fastest and maximum muck consumption then, using muck reducing bacteria along with an aerator will indeed provide exponentially faster muck reduction results. To better understand this and to see the solid proven data of this topic, please see the link below to a recent field study and evidence which was done using Airmax MuckAway in Rochester Hills, Michigan:
https://www.airmaxeco.com/product/muckaway-study/field-studies
I hope you find this to be helpful and have a good day!
The link is to a marketing publication and not to a study – has this study been published? There were no link in the marketing piece. So this is not ” solid proven data”.
The references study did include tubes that were aerated and should have provided enough oxygen.
The study was for 60 days and you say that it takes 90 days. But surely if it is working it will start reducing muck right away and then keep reducing it over time. Thicker layers might take longer, but to say there is no reduction until day 90 does not seem to make sense?
Are there published studies that show such products work?
I have a half acre natural spring pond with constant in/out flow. Have lots of chara and fall tree leaves which inevitably creates muck when it dies each year. Any experience or testimony from using a Muck Razer to roll and stir up the muck to increase decomposition. We do have 2 aerators which do help keep water oxygenated for our fish.
My pond has a bottom drain and filtration that removes the organic matter and fallen leaves. Zero muck.
To me, those products are wishful thinking. Sellers wish to make money, and buyer wish for an easy way.
Don’t know how to write to you in proper way, so I’ll ask here : could you please evaluate the benefits, if any, of using micro rhizome innoculant in planting holes. Thanks
https://www.gardenmyths.com/buying-soil-probiotics/
https://www.gardenmyths.com/mycorrhizae-fungi-inoculant-products/
Surely if you have wildlife in your pond, in my tiny pond I currently have tadpoles, then the pond is healthy and shouldn’t be interfered with too much. I constantly remove duckweed and occasionally remove a few handfuls of pond weed.
I have a narrow wetland going through our property. It grows a lot of algae. I remove some of it daily because I read that it depletes the water of oxygen and we have a lot of frogs. I can see the oxygen immediately after I remove it. But, is there an easier way. It’s a lot of work.
“I can see the oxygen immediately after I remove it” – oxygen is invisible – nobody can see it.
Algae depletes oxygen at night.
Haha! But those are anaerobic bacteria. Once the septic tank is involved, there’s some air involved, at least at the surface.
What are anaerobic bacteria???
Most situations have both types of bacteria and some are even facultative anaerobes.
I wonder if this holds for septic tanks as well? Clearly, there aren’t any plants in that mix.
I suspect it does. Shit is full of bacteria – why would you need to add more?
This analysis seems completely reasonable. It is why we didn’t get the treatment for our ponds. I was wondering do pond aerators and bubblers work? I hear they do but work best in the night after the sun goes down. What does your research say?
I have not researched them, but they should help. They add extra oxygen and move organic matter to higher levels where aerobic bacteria can decompose it. I can’t think of any reason why they work better at night for muck removal, but oxygen levels are lowest in a pond at night, so it will help with that problem.