Pond muck- any tips on removing it?

I have a nice little spring fed pool/pond, approx 30x30 feet, but being in a deciduous forest it's got a lot of muck from all the leaves that fall in. So even though the water has decent clarity, any disturbance to the bottom stirs up foul smelling muck which keeps me from wanting to develop the it as a natural swimming hole.

There are various products out there. Some are enzymes or bacteria that help digest the muck. Has anyone used any of these or have any other suggestions to clean this up a bit?
It sits low in a very steep sided area so mechanical removal is not possible :(

Matt Todd wrote:...or have any other suggestions to clean this up a bit?

How hard would it be to access electricity from there? Is there room for a veggie or flower or perennial bed? Or a hugel? I think a trash pump, a bucket with holes drilled in it, and optionally a used garbage disposal would let you remove the material from the pond, but not from the site (and also use the nutrients). Or you could pile it around a willow tree. (A new use for Paul's willow bank!)

I think it only smells bad because it's anaerobic. Putting it where the water can drain out, and either turning it to aerate or spreading it thin enough for oxygen to penetrate would probably get rid of the smell, probably in a day or so. Or pile it up, let the top become aerobic, and don't disturb it until it breaks down so you're never exposed to the anaerobic smell.

Or a chinampas. (No idea if I spelled that right.)

My first thought was to add aeration to the pond with a waterfall over oyster or muscle shells.
If the 'filter bed, or bio filter' is kept continually wet with flowing water it develops bacteria that helps the pond water.
Even if you could cause the spring to run over the filter bed that would also help.

Sometimes the beds may be called a 'Fluid bed', using filtration technology.
This involves sending water into a basin filled with bio media.
The water and air rolls and tumbles across the media.
This provides a highly oxygen rich environment for the media to grow bacteria. Also, the tumbling media remains clean of debris.
All bio filters work best with highly O2 saturated water and clean media. The fluid bed is the best at providing this.

The best way to aerate a pond is to constantly draw water from the bottom of the pond and return it to the top.
This takes the poorly aerated water at the bottom and sends it up to come in contact with the oxygen at the surface.
Constant circulation, 24 hours a day, is needed to maintain proper aeration in a pond.

An additional way to aerate a pond is to use an air pump and air stones. The air stones are placed at the bottom of the pond and they create a rising column of air bubbles.
Similar a waterfall, the bubbles themselves don't add much aeration, but what they do is create a water column bringing water from the bottom to the top,
where it can get aerated at the surface.
So you improve aeration and circulation at the same time!

Air stones are also an easy way to temporarily add a boost of oxygen to your koi pond in the summer months. As the water warms up it is unable to hold as much oxygen. So you will want to give the koi as much oxygen as you can. A small air pump and a few stones are a quick easy way to vastly increase the oxygen levels without performing any major construction on the koi pond.


The number one cause of bad pond smells is due to a lack of water aeration, which usually results in a strong smell of rotten eggs. A pond needs to have some level of water movement or it will eventually begin to stagnate.
Aeration provides a pond fresh oxygen, nutrients, and water flow, which helps prevent a build-up of substances in any one area.
The smell is often noticed during Spring when water begins to naturally circulate due to temperature and weather changes.

I searched this and came up with some interesting things;
Fix a dirty pond

Nasty pond smell

Solar powered aeration

EXPLANATION OF BIO FILTERS

Biological filtration is something every koi pond requires. It is a natural process that will happen all on its own if the proper environment is provided. The basics of how biological filtration works are pretty simple, but providing the perfect environment to maximize your filters potential and provide the best water for your koi is where things get difficult.

The biofilter will grow two types of bacteria. Nitrosomonas bacteria that will oxidize ammonia into nitrite, and Nitrobacter bacteria that oxidize nitrite into nitrate. These are generally referred to as “beneficial bacteria” or “aerobic bacteria”. This bacteria will naturally form on all underwater surfaces of a koi pond assuming two main ingredients are provided, oxygen and ammonia. The ammonia is easy, the koi produce this in their waste and it will also come from decaying plant material. But oxygen isn't as easy as you might think. If the koi pond is lacking O2 then that wonderful healthy aerobic bacteria turns into anaerobic bacteria which can quickly kill your koi. For more on how to properly aerate your koi pond, please read Aeration in Koi Ponds
The basic process goes like this. 1) the koi produce ammonia. 2) the Nitrosomonas bacteria converts the ammonia into nitrites. 3) The Nitrobacter bacteria converts the nitrites into nitrates. Then 4) the nitrates are consumed by plants and algae which the koi eat and start the process all over again. Every underwater surface will grow these types of beneficial bacteria all by themselves. In nature, there is more than enough surface area to handle the amount of waste present. But in natural lakes and rivers, there are usually millions of gallons for every fish. However, in our koi ponds, we have a much higher stocking density than is found in nature so we need to provide a lot more surface area than just the sides of the koi pond. That is where you bio filter comes in.
All a biofilter does  is provide lots of surface area to grow bacteria, that's it. Nothing magical or mysterious about it.
Biofilters provide lots of surface area in a small space, effectively capture and remove waste and are easy to clean. But really it all just comes down to surface area.

So back to that ideal environment,
One thing that bacteria needs are lots of oxygen. In most cases, this can be accomplished simply by sending the water through the filter continuously. That means never turning off your pump.
If you run your pump only a few hours a day to save electricity, then you deprive your bacteria of its much-needed oxygen. The bacteria will die off very quickly and turn from aerobic into anaerobic bacteria.
So this causes two problems.
A) the filter is no longer able to convert the ammonia produced by the koi and
B) all the toxic anaerobic bacteria is flushed into the pond as soon as you turn the pump back on.
So one crucial element for an effective and functioning biofilter is a pump that runs 24 hours a day and is turned off only when servicing the koi pond.

The next element to a well-functioning biofilter is clean media.
The next thing you need to consider is the amount of media you need in the filter.  It is always best to oversize your filter.
The filter will not grow more bacteria then there is dirty water present in the  pond, so just because you have a big filter, doesn't mean you have more bacteria.
But by oversizing the filter, it can grow additional bacteria quickly if it is ever needed.

5 reasons to aerate a pond

Pond filtration systems

John C Daley wrote:=
The best way to aerate a pond is to constantly draw water from the bottom of the pond and return it to the top.
This takes the poorly aerated water at the bottom and sends it up to come in contact with the oxygen at the surface.
Constant circulation, 24 hours a day, is needed to maintain proper aeration in a pond.
=

Thanks for all that wonderful and detailed information. I took the time to read it over, a few times actually!
The spring water is basically coming in one side of the pool directly from the edge so I cannot take advantage of natural flow over any filter medium there.
I did notice a big difference between early spring-time and being down there yesterday (mid summer here) I feel like the natural bacteria had "woke up" and clarity/smell were both much better. Plus a big rain event likely "stirred the pot" quite a bit.

My plan for now is to make a simple weir with concrete blocks so I can use a sump pump to get some of the water out. That will allow me to remove some tree branches and make sure there's no surprises under the water that I can't see. I also feel like I can use the water coming out of the pump to spray the murky bits of organic matter around the edges and get them agitated so the natural bacteria can get at them easier (plus some of the stirred up water will get pumped out and replaced by clean spring water.)

I believe I understand that I could add one of those natural bacteria products, but that a biofilter does do the same thing (plus the pumping action of a filter would circulate the water.) This is all 200 feet away from power so I will be seeing how far the sump pump on extension cords gets me, then eventually I hope to get permanent power ran down there and I can start utilizing some of your suggestions like air stones and/or filtration. No fish currently, but someday if I add them I will definitely wait until I can filter.  

Thanks again. Funny that I had just looked up Bendigo on a map before your response! We have this view of Australia here as the red dirt outback, but so much of the populated areas look just like our own rolling farmland in central USA.

The stuff in the bottom of your pond may seem like muck or something unwanted to you, but it may be what is keeping the water in your pond so it doesn't just empty out.  It is also the home for the critters who are keeping mosquitoes out of your pond.  That becomes crucial for being around it.  

A healthy small pond is not really a place to swim, since the ecological balance of it involves the muck at the bottom, which will always have an anaerobic smell in all ponds, since it's underwater, and the plants around the edge that are home to other critters that help keep mosquitoes away.  

30x30 is not really big enough to swim in?  A couple strokes and you'd be across it?  It does sound like a nice spot for a dock and a rowboat, do some floating, dangle your feet in.

Adding any kind of biological digesters might change the whole balance of it.  Unless it's filling up and it becomes a marsh that needs to be dug out again, it might be better to just let it stay natural.

Here is what I'm finding with the pumping/cleaning. I spent the weekend pumping out, and when I had it close to empty I turned the spray back on the inside to disturb the mud and muck so it would suspend in the water before being pumped out again. Water is usually much more clear than this, just opaque due to my disturbance. No big surprises, just a rusty bucket and a little glass raked out of the bottom. Easily 6 feet deep in the center, nice limestone formation on the south side.

I was amazed that after turning the pump off, it re-filled with just spring water (no rain) in just 20 hours! My slipshod estimates are around 500 to 600 gallons an hour of flow.  So at this point I don't believe I need a filter. The springs flow in on the left side and exit at the right, so maybe just a nice bubbler to keep thing oxygenated and moving would be enough for improved clarity. Either that or a small pump set up to draw from the bottom and draw water up to some rocks I could stack in such a way to make a little water feature.

Not sure if I mentioned that this "hole" is only here because a culvert under a railroad grade has been delivering rain water to scour it out for about 150 years. Culvert is 12 feet above water level on the left side, which shows you the power of erosion since this all would have been 12 feet higher in 1872 when the railroad grade was created.

Cristo Balete wrote:The stuff in the bottom of your pond may seem like muck or something unwanted to you, but it may be what is keeping the water in your pond so it doesn't just empty out.  It is also the home for the critters who are keeping mosquitoes out of your pond.  That becomes crucial for being around it.  

A healthy small pond is not really a place to swim, since the ecological balance of it involves the muck at the bottom, which will always have an anaerobic smell in all ponds, since it's underwater, and the plants around the edge that are home to other critters that help keep mosquitoes away.  

30x30 is not really big enough to swim in?  A couple strokes and you'd be across it?  It does sound like a nice spot for a dock and a rowboat, do some floating, dangle your feet in.

Adding any kind of biological digesters might change the whole balance of it.  Unless it's filling up and it becomes a marsh that needs to be dug out again, it might be better to just let it stay natural.

I am trying to find the balance between big disturbance and gentle changes. My post above is an explanation of how this all came to be, which was not a natural process to begin with :)
Really just trying to make a nice place to take a dip as we get into the 100 degree heat of summer. Just being down in the lower area is nice an cool. I need an adult clubhouse down there!

Any aeration you can provide will help.  Any filtration you can provide will help.

If I understand you correctly (forgive me if I'm wrong) you've decided that the current from the spring flowing through the pond is going to be enough.  I do not believe it will be and you will be back in this same spot in six months from now after the leaves fall and mat up on the bottom.  The current is horizontal and mostly near the top.  You need a pull from the bottom, out of the pond (where the oxygen is), then back in.

Even a small container filled with pea gravel with a hole in the side to drain water back in the pond will make a difference.  Particularly if that container has plants in it. I use a solar pump-to container-back to water approach often.  To be honest it fails a lot, either the panel or pump fail.  But it is still better than nothing. A mains powered pump really makes a difference.

Even if you do none of the above things, one change you can make is to stock the pond with aquatic plants.  At that size pond you could get some nice lily pads going. Their roots will take up a lot of the nasties and convert them into plant. :)

ETA: I missed this, which is definitely the right way to go.  "Either that or a small pump set up to draw from the bottom and draw water up to some rocks I could stack in such a way to make a little water feature. "

Rob Lineberger wrote:Any aeration you can provide will help.  Any filtration you can provide will help.

If I understand you correctly (forgive me if I'm wrong) you've decided that the current from the spring flowing through the pond is going to be enough.  I do not believe it will be and you will be back in this same spot in six months from now after the leaves fall and mat up on the bottom.  The current is horizontal and mostly near the top.  You need a pull from the bottom, out of the pond (where the oxygen is), then back in.

Even a small container filled with pea gravel with a hole in the side to drain water back in the pond will make a difference.  Particularly if that container has plants in it. I use a solar pump-to container-back to water approach often.  To be honest it fails a lot, either the panel or pump fail.  But it is still better than nothing. A mains powered pump really makes a difference.

Even if you do none of the above things, one change you can make is to stock the pond with aquatic plants.  At that size pond you could get some nice lily pads going. Their roots will take up a lot of the nasties and convert them into plant. :)

ETA: I missed this, which is definitely the right way to go.  "Either that or a small pump set up to draw from the bottom and draw water up to some rocks I could stack in such a way to make a little water feature. "

Lol, I started looking in to shade tolerant aquatic plants yesterday and had to stop myself. I've devoted way too much energy to new plants this spring and I need a dang break!
Plus I'm concerned about a major rain event destroying things I develop down there, which is the subject of another thread on this area: https://permies.com/t/142672/slow-storm-water-flow-culvert#1116919

But I like and appreciate your suggestions! Will definitely look into planting next year. I do wonder how much shade a solar pump can handle. The summer shade prevents algae... just doesn't leave a lot of sun for solar.

Matt Todd wrote:

Lol, I started looking in to shade tolerant aquatic plants yesterday and had to stop myself. I've devoted way too much energy to new plants this spring and I need a dang break!
Plus I'm concerned about a major rain event destroying things I develop down there, which is the subject of another thread on this area: https://permies.com/t/142672/slow-storm-water-flow-culvert#1116919

But I like and appreciate your suggestions! Will definitely look into planting next year. I do wonder how much shade a solar pump can handle. The summer shade prevents algae... just doesn't leave a lot of sun for solar.

A solar pump can't handle any shade.   Maybe for a bit but eventually when your batteries are out, you're left with nothing.  If it's shady, forget it.

Plants, then.  Or get electricity down there. Good luck!

Does the culvert give you a bit of constant or nearly constant flow with fall?  Or if the spring running out has fall with that might work too.

Suggest looking at trompe pumps as a possible no power air source if you can get the flow.  Done properly this would be no moving parts.  If it powers a fish tank stone down deep inside a pipe to form an air lift pump you could get it both air and circulation out of the same pump.  Just need an air pressure source which the tromp could give you.

Another possible would be a ram pump.  You can bet both flow and air from it if you build the snifter hole correctly.  Disadvantages are complexity and moving parts.


Growing up with a number of reservoirs had 2 reservoirs that were favorite swimming holes.  The first was a smaller dead end reservoir.  The water backed up and went else where when full.  It was roughly 4 feet deep.  It was different because it had a number of really large carp that lived in it.  The water was always brown with mud.  But the mud had almost no odor and the muddy water mostly kept any water weeds from growing.  So could you add some big carp and block their ability to swim out?  The second one was a fairly large 15 foot deep irrigation reservoir.   It was drained and dried up once a summer.  That killed the water weeds back and mostly eliminated summer odor of any kind as well as keep the mud firm.  The water got stinky in winter but that was preventable too.  A couple of patches where the snow was removed anytime it snowed  (each about 10 ft x 10ft) would let enough sunlight thru the ice to keep some plants growing which kept the water far better.

One final comment.  If it is growing algae you will find the algae worth harvesting to mulch around plants.  It is one of the best water retention mulches you will find as long as it remains undisturbed.  It is very fragile dry so if you have animals they will likely destroy it.  By removing the algae for benefit you reduce the organic load to make stinky mud/water.

C. Letellier wrote:Does the culvert give you a bit of constant or nearly constant flow with fall?  Or if the spring running out has fall with that might work too.

Nope, the culvert comes out of a dry wash. No flow unless there is a good rain, and even that doesn't last long. And the spring is underwater so no fall there either. I'd love to have some kinetic energy of falling water to play with!

I appreciate your thoughts on the rest of the post. Never thought about harvesting algae. I may indeed implement a regular spring draining (pumping) to help get the yearly accumulation of sediment out.

Update: Aeration works! I ran a pump and aerator from Practical Garden Ponds the last two seasons and it clears the water right up. Starts out very green in spring since the sunlight can reach it and promote algae. But as the leaves grow in and the pond is shaded, the combo of bubbles and shade really clear it up. Granted, this probably only works because the constant inflow of spring water. Also, I used cattle panels up before the culvert entrance to catch trash and natural debris so they don't enter the water.

I learned not to put too much infrastructure in the "hole." We had a freak 13" rain storm last season that dramatically re-shaped things through erosion and land-slides... but ended up making it easier to access (while also nearly blasting my inflatable loungers into the next county and burying my pump in mud.)

This weekend I moved some limestone rocks to make it even easier to have a place to sit and a way to get in the water via rocks rather than mud. Here's the current vibes swimmin' hole vibes:

https://youtu.be/qQ_ZrmPClsQ

Glad to hear the aeration is working! If you are interested in further clarity and further permaculture options, Missouri has a number of native shellfish; more info here: https://mdc.mo.gov/discover-nature/field-guide/freshwater-mussels
The shellfish are filter feeds and, in some cases, can dramatically improve water clarity. Plus, your swimming hole could double as a source of food and mother of pearl!