Pond Boss Forums AERATION Should I aerate? Don't assume aeration will fix any of your issues

You should all be happy to know that "Analysis and case studies of enzymes and bacteria used to manage sediment, algae, and weeds" is a proposed topic for the upcoming NALMS symposium in October. Hopefully there there will be some light shed on this topic. Sue, there is a call for papers for this symposium. Perhaps you could submit your study. See the following link:

http://www.nalms.org/pdf/2009%20Symposium%20Call%20for%20Papers,%2002.23.09.pdf

Also, I have put in an inquiry with the environmental engineering department at our local college (and my alma mater) Cal Poly San Luis Obispo to see if they have any students that would be interested in taking on such a study as a sr. project or masters thesis. I offered to provide aeration, bacteria, sludge judge, etc... and even the boat to any student interested. We'll see if anyone bites on this offer.

We're a while off from submiting research, but will definatly be interested in hearing the talk at NALMS. Thanks for the heads-up!

Oh, one more thing. There are plenty of case studies conducted by the companies that make and sell the bacteria. And yes Cecil this is done specifically to boost sales. However, I think the operative words in this discussion are "peer revised" as I get the feeling that some of the more skeptical people out there are not going to take the word of the people that make and sell the stuff.

This is why this forum is so good... People like Sue, The Wizard and Cary who although they have companies and sell products IMO are good honest people who are trying to help people out while also making a living. No trying to sell people stuff just to make a buck. Top notch!

Agreed

Well I'm surprised to see there are case studies but if you say so I believe you. I've got several pond supplier catalogs and not one offers a case study. Not doubting you at all but I just haven't seen one.

That said I look forward to the impending research.

Yeah, that oughta do it.

I agree with Sue. Lots of claims but very little scientific data.

Update on my inquiry with Cal Poly SLO: This morning I received a phone call from a professor in the Environmental Engineering Dept. regarding my inquiry about a study on sludge digestion via bacteria. He expressed a lot of excitement about the project as he is very involved in studying the application of bacteria to break down specific pollutants such as MTBE's at oil contamination sites among others. He says he has several grad students that would be interested in this project. I will be meeting with him next week to discuss more details of the project and of course funding.

I encourage anyone who is interested in this topic to provide input on how we can make this study as useful and credible as possible.

A few things that we discussed this morning:

1. Testing will take place in jars rather than ponds in order to isolate the variables.

2. Sludge samples will be taken from several locations throughout a pond known to receive "natural" runoff such as leaf litter and perhaps urban runoff as well. Sludge samples will be thuroughly mixed into one composit sample to be tested.

3. Relative reduction of sediments will be based on weight (Total Solids vs. Total Volatile Solids) rather than volume since the biproduct of bacterial digestion can produce a very light & fluffy floc that tends to settle on the surface of the thicker sludge.

4. Bacteria will be provided different environments such as aerated vs. unaerated, bacteria vs. no bacteria, stirring vs. no stirring, different temperatures & pH etc...

5. Different brands of bacteria will be used

I'm open to suggestions so please share your thoughts with me.

Richard, I highly recommend that you contact Bill Cody for his input, I think that he can give you some feedback regarding this study.

Species, strains of bacteria and specific enzymes should be documented to indicate if the bacteria are different that those already naturally present in most water bodies. The biggest unknown to date is which bacterial strains are used in each product (truth of advertising). How does adding bateria species that are already present enhance the existing bacterial community? Pickle Jar ecology is not the real pond world, but it is a start. IMO one can often easily achieve desired results in controlled jar or micro-mesocosm studies.

I may have missed something here but the OP said he has 3 bottom diffusers, what kind of diffusers? Some types of diffusers aren't very effective and the system may not be matched to his size pond.

My experience with adding bacteria is that it does work in the shallows and it's the only thing you can do to reduce muck if you don't have an aerator. Without an aerator you have to add bacteria at regular intervals, not just once. When I first started adding bacteria (prior to getting an aerator) there was an obvious change in the color of the pond bottom after only one month. My dogs were also much cleaner after swimming. After one entire summer of using bacteria the pond bottom in the shallows looked like it did when it was first dug.

This is my first summer with an aerator and I only added bacteria at start up because I had some left over. It's my understanding that you don't need to add bacteria if you aerate and I believe that to be true. My pond is much clearer now without adding bacteria and I can see more of the (clean) pond bottom.

My unscientific conclusion based on observation is that bacteria alone does work (at least in the shallows) but aeration alone is superior for cleaning the pond bottom

Thanks for the input JHAP and BC. Indeed the strains and communities of bacteria will be very important to determine both in the supplements and the sludge sample. The idea of doing the testing in jars was to isolate the variables rather than to achieve a desired result. It's tough if not futile to isolate variables in a pond, but again I'm open to suggestion if anyone has some ideas. And, to be honest we don't have a desired result, we just want to see the results and share them with the lake/pond management community regardless of the outcome of the testing. Although I am already a believer, I would gladly be humbled to learn that the truth is other than what I believe it to be.

As an interesting side note, the professor I've been speaking with has noticed that in his bioremediation projects for oil contamination, some sites have existing bacteria in the soil that readily break down the pollutants. Adding bacteria to these sites does not appear to enhance or speed up the breakdown. Other sites do not have the same community or quantities of naturally occuring bacteria. These are the sites that are experiencing enhanced breakdown with bioremediation. Maybe not all ponds have a "healthy" community of naturally occuring bacteria. Of course, if this is true, the next questions are why aren't they there and will the store bought bacteria be able to thrive there.

In a side discussion at the last Pond Boss conference several of us discussed the possibility of a test similar to what has been discussed.

The plan we formulated would have been to gather a certain quantity of muck, mix it throughly and weigh and divide into as many equal parts as you had bacteria, etc. to test.

Then place the muck in five gallon containers, add water and bacteria/enzymes, etc. and let set outside for some time. We discussed treating each container the same, stiring so often, etc.


I believe we felt it would be ideal to add bacteria, etc. based on cost, so the same $x.xx of material in each test bucket.

Finally drain and weigh each container of remaining sediment and determine which had lost the most weight. I think this is approximately what is being presented here, except we thought putting it in five gallon "pickle" buckets would allow you to test a larger sample.

Bing

Hey everyone. It's been a while since I've been here. Sue's kept me pretty busy this summer. In the past I've had abundant opportunities to work with both marine and freshwater bacteria concentrates as they apply to very large, enclosed systems (public aquaria type settings). What I can tell you is that the bacteria that I used significantly reduced the amount of nitrogen, and muck buildup in a good portion of the filtration.

However, I need to qualify that by saying that these systems, just as any natural ecosystem, have a natural carrying capacity for every trophic level in it. The bacteria we used may or may not have been the same species as what was already in the system (I didn't perform any research on the topic, just noticed and can report on the results). The reason for adding the bacteria was also different in these circumstances. It was generally used for "quick start-up" or emergency "dangerous nitrogen level" situations. These situations would generally not apply to the pond community. They were added to temporarily BOOST the nitrification and detoxify the water, in order to save the fish. A side effect was the reduction of muck that had built up in well seasoned systems.

I mentioned the term carrying capacity earlier. Let me elaborate. Due to the fact that even a large pond is a relatively closed system, it will have carrying capacities (maximum sustainable numbers) for all of the species it contains. This includes everything down to the bacterial level also, and is influenced greatly by physical circumstances that put limits on what can survive, and in what numbers. A natural checks and balance system.

Bacteria reproduce very quickly. Their life cycle is generally very short. Most new pond owners are not in such a hurry to get things going that they have the need for "jump starting" the pond when it will only help them by a matter of a few weeks. In the same respect, most ponds will not experience a catastrophic nitrogen spike overnight (unless SIGNIFICANTLY OVERSTOCKED ALL AT ONCE).

The nice "side effect" that seems to happen, at least in my experience, is that there is a slight muck reduction by using the type of bacteria that I have, in the past. I'm not sure if these are the same species of bacteria that are available for the pond scenario, but it would stand to reason that they would help in that respect, to some degree. Further research is definitely warranted in order to gain quantitative data.

To address Loretta, the reason that your bacteria worked in the shallows (without aeration) is because these bacteria are aerobic, and require certain levels of oxygen to survive. Your pond is most likely stratified to some degree, preventing decent oxygen levels in the deeper areas, and therefore preventing the muck reducing bacteria from being able to reach the muck in the deeper areas. This is why aeration helps. Properly sized aeration will circulate the water from top to bottom, bringing the oxygen levels in the deeper areas up to sustainable levels for the bacteria to survive and start breaking down the muck.

Once the pond is de-stratified, the natural bacteria of any pond will quickly reproduce and begin to break down your muck for you. However, depending on other parameters of your pond, "quickly" can be a few months to a few years. Bacteria are very pH and temperature sensitive, and significantly slow down or stop when exposed to parameters that are outside their "norm".

The reason people have to keep adding bacteria, as you mentioned, is most likely due to the fact that their pond is already at the carrying capacity for that type of bacteria, and after some time, start reducing in numbers again, in order to get back to the natural maximum sustainable number for that species.

While I personally don't disagree that the addition of bacteria can help, I question the generally huge expense associated with it since a pond with decent circulation and oxygen levels to the bottom should be able to maintain a healthy population of muck reducing bacteria on its own. But as I said, I do think that more research is CERTAINLY warranted.

Hope this sheds a little light on the subject.

This would tell you the most cost effective material but it wouldn't tell you the most effective bacteria. To determine the most effective bacteria you would have to determine what the organism concentration or count is. Probiotics list this information on their product label but pond bacteria does not. Contacting the manufacturer may be an option if determining the best bacteria is your goal but then again any of the information that you obtain from your samples will only be applicable to your particular water sample and it's conditions (pH etc.)

I wouldn't stir the samples at all. If someone is going to aerate then they won't need to add bacteria.

JMO

More bacterial food for thought.

One thing that has not been mentioned, or if it was, I missed it. IME, aerobic bacteria constantly need a fresh substrate to grow on. When even a colony of aerobic bacteria die on decaying matter, well oxygenated water is prevented from reaching the detritus, including most anarobic bacteria. Until a fish or wind and wave action disturb the dead colony and break the "seal" to allow fresh growth, little more bacterial digestion occurs.

In my heavily stocked aquariums, when ammonia levels rise, I merely disturb the dead bacterial film on my bio-filters and the fresh bacterial growth quickly reduces the levels (quickly = within 3-5 hours). My sand filter, where the substrate is continually disturbed has never had a slow increase in ammonia. I often add 10-15 pounds of fish at a time in this 150 gallon tank. The resulting spike in ammonia and nitrates rarely lasts more than a day before levels are brought back to zero. 18 pounds of fish and nearly a half pound of food per day is pretty much the upper limit for control in this tank as ammonia will not drop below 2ppm at this density.

Good post Doug,

I called several bacteria companies including one that I attended a training class with in Canada. They all stated that if one were to provide samples of both water and substrate (with muck) that they could engineer bacteria to match or (supplement) what is missing. Of course this is custom blending bacteria for every case and will be much more expensive.

I recall a project that had an old saw mill along the lake bank and train tracks that led to the middle of the lake. Every week the mill would send a train car full of saw dust and dump it in the lake. This was about 60 years ago.

Now the residents wanted to reduce the muck levels and we sent a bottom sample to the bacteria company to break down what the muck was composed of (wood pulp) and a bacteria was custom blended to work on these areas. Adding the bacteria with aeration was the only way this would work since a definate thermocline was present and oxygen level were below 1 mg/l

During my stint at Sea World, we used to add "donar" gravel from already established aquariums to jump start the bacteria cycle. I agree with Doug in that once the optimum carrying capacity has reached the bacteria will stop reproducing and the next strain of bacteria will beging to work. Case in point the cycle an aquarium during start up...fish are introduced and the ammonia builds up. The first strain of bacteria brings the ammonia down. Next Nitrites begin to spike. The next strain of bacteria take care of the Nitrites. Finally the Nitrates begin to rise which is not too dangerous for the fish as the other two and can be lowered by simple water exchanges (in a pond, rain and evaporation).

This topic should be one of those post that are archived. This has been a great conversation between everyone!

This makes a lot of sense to me and seems to tie into Bill Cody's presentation at Pond Con 2. IIRC what Commander Cody said, in his specific experiment, stirring the sediment had more effect than adding bacteria and not stirring.




This also makes a lot of sense to me, an engineered bacteria to deal with a specific type of pond muck.

So a little help for a complete amateur, I understand where aeration will both destratify a pond and oxygenate the water, and if designed and implemented correctly will oxygenate water that is at the bottom of the pond. So my questions are:

1. Will aeration alone stir up the muck sufficiently to expose "new" muck to bacteria?

2. It seems to me that unless you added something artificial to a pond (like the saw dust that Cary mentioned) that bacteria that would eat the muck that was in a particular pond would be introduced naturally. I'm not explaining this very well (not enough coffee yet) but here's what I'm thinking....a decaying leaf is on the ground, it must be covered with the bacteria that helps it to decompose, it gets blown into the pond and sinks, the bacteria, if provided oxygen, would now be in the pond, correct? Or are the bacteria that grow in ponds completely different that the bacteria that decomposes the leaves on the ground?

In my non-scientific way of thinking, an occasional stirring of the bottom (I don't have a clue how this would be done on a larger BOW) would have as much or more impact than adding more bacteria.

But I'm not a science guy, so it is very likely that I don't even know the correct questions to ask. Fortunately, I have no aversion to asking stupid questions.

Interesting stuff Carey. It's amazing what was acceptable years ago, isn't it?

Custom "blended" bacterial slurries sound extremely expensive, but I don't have any frame of reference for that.

Through my testing in the lab here in Florida, I haven't run across too many situations that have nitrogen problems, unless there's been a spill of some sort or as a result of a massive fish kill caused by something else (oxygen levels usually). My point was actually that it was a neat "side effect" that added nitrifying bacteria either also worked on the muck, or altered the situation enough for another strain to work on it.

As for water changes, ponds don't really get true water changes unless they are drained and refilled, or are fed by some source and have a spillway. All rain and evaporation will do is dilute and then concentrate the waste products in the pond. Evaporation is only water vapor, not the waste products. They stay in the pond as the water evaporates (kind of like boiling salt water and ending up with salt in the bottom of the pot). What you need in order to do a true water change is a way to physically remove the waste products as well, and then bring in clean water. But most ponds have more than enough bio-filtration naturally and would never need a water change.

Ok, that is what I get for posting a comment at 0500 in the morning! I was typing without thinking it through. Yes, I mis-typed when I said that ponds are achieving water changes by evaporation...that is grammer school science class. Concentration of items in the water increases as the water is evaproated and is diluted when a rain event occurs.

After looking through my notes from that bacteria seminar I attended and speaking with our bacteria supplier here is what I have:

Bacterial/Enzyme products improve water quality by increasing the biological diversity and/or activity in the water body. As I mentioned earlier, special microbial cultures are generated for specific applications. (Saw Dust wood pulp)

The select bacteria produce enzymes to break down organic material into water soluble nutrients. The bacteria then digest the released nutrients, multiply and produce more enzymes to continue cleaning the entire system. A large biological mass develops which has the capacity to digest large amounts of organic waste. This mass will only be as large as the water body allows like Doug said earlier. The digestion process of the microorganisms ultimately results in the production of harmless carbon dioxide and water.

The type of enzyme produced by the bacteria is dependent on the organic waste that it will break down:

1. Protease enzymes digest proteins;
2. Amylase enzymes digest starches;
3. Lipase enzymes break down fats, oils and grease;
4. and Cellulase enzymes digest paper and cellulosic fibers.

Because bacteria and enzymes work together in the digestion process, the selected blend of the two is what is very important. The enzymes jump-start the digestion, while the chosen strains of bacteria produce more of the specific enzymes necessary to digest the particular type of organic waste in the system. **Can't put the cart before the horse.**


The idea of seeding an organic system with microorganisms having specific characteristics is well established for industries of fermentation. These areas include processes for the manufacture of antibiotics, cheese (both aged and cottage type), yogurt, wine, beer and even pesticides. I also mentioned Aquariums earlier today.

Bioaugmentation is the process of inoculating specific microflora into a given environment to enhance certain biochemical processes or to jump start desirable changes in that environment.

Bioaugmentation that is found commonly in wastewater plants usually involves a specific microbial product added at levels ranging from 2.0 to 8.0 parts per million (mg/l) times influent volume. Of course the dosage depends upon the type of waste to be treated, environmental parameters of the water, how long the water stays in the system and design of the system.

Just like in the wastewater pond above, the environmental parameters, or factors affecting the performance of the microbes, are essential to the success of the product in normal fish and detention ponds. The environmental parameters of the system include:

1. pH,
2. temperature,
3. dissolved oxygen (DO),
4. biochemical oxygen demand (BOD),
5. chemical oxygen demand (COD),
6. total suspended solids (TSS),
7. carbon,
8. nitrogen,
9. phosphorous ratio (C:N:P)
10. detention time.

These microbes require neutral pH, warm temperature, plenty of oxygen, appropriate nutrients, and time to degrade the organics.

Because this information is almost never attained, and the cost of a custom blend of bacteria and enzymes would be so large that no one would ever purchase it, the growers of bacteria had to make generalized assumptions on the majority of pond conditions found and create a blend that will work in most applications. That being said, microbe bioaugmentation is just another tool in the preverbial "Aquatic Tool Box".

Suggestion: while researching for products, compare them on their bacteria count (aerobic, anaerobic, facultative and total plate count), type of enzymes present and cost per application.

The microrganism within a system are constantly undergoing changes in both numbers and types of microorganisms represented in the population. These changes are affected by environmental influences such as temperature, sources of carbon or nitrogen waste, heavy metal concentration as well as other toxic substances, dissolved oxygen levels, and many other factors.


Given a sufficient length of retention time in ponds proper conditions for oxidation of the waste, bioaugmentation can be used as another tool to increase the efficiency and reliability of treatment.

Ok, I spent way too long on this with binders and notes spread all over my desk...time to get back to work. Thank you everyone for reading this over and now go and get yourself some yogurt, cheese and have some fried murell mushrooms...you'll have your three main food groups...bacteria, mold and fungus.

Great posts Cary and Doug and great informative dialogue on everyone's part. We can all learn from eachothers experiences. Keep sharing!

I have three 1/3 HP Vertex "AirStations" and a 1/2 HP Kasco surface aerator. Pond size is a little over 1 acre. Deepest is around 9 Ft., Avg is around 4-5 Ft.

Dang Steve! you might want to have Sue Cruz map your pond from an aerial shot. Yo may have a little too much water movement. IIRC, that can cause some problems too for some species.

BTW, are you going to make the conference?

Hey Rex
Doesn't look good for the conference, I'm working too much
As far as the movement, the surface agitator causes some apparent movement but nothing too crazy, more so within about 10 ft of it. It's not enough to drift my bobber and obviously not enough to curb my duckweed. I look at the small boils from the bottom aeration and always think, "Is that really doing anything ?"

Ps. I saw your post on the Tilap forage and the wheels started turning again. I've caught some bass in the 12-14" range which looked skinny to me. I caught a 5 pounder which my neigbor decided to transfer from the big lake in the early summer (without my knowledge), he was by no means, skinny; The boy seems to be eating quite well.

rainman this is not too much water movement with the shallow depths. Steve I know your system was desigend well by Shaun and while it is a huge benefit as you know it does not fix all issues. Also to fix nutrient issues might take longer than it has. I still think the best course of action is the use of flouridone.