Pond Boss Forums AERATION Systems questions bottom cleanup

I have just set up a 1.5 cfm pump to 1 diffuser in 9 ft of water to clean up muck, mostly decayed leaves from the 20 yrs. of saplings growing and more leaves falling. Its not in bad shape, considering. A few inches of soft bottom. The pond is not stocked, is 300-350,000 gal.(1/3 ac.)
What would be av. and worst case for time frame of running compressor continuously, to get the pond cleaned up to stock at least a few CC, then later some BG, a few LMB for predation.
Pond is in S. Miss. I figure at bottom end of diffuser efficiency, 5-600 gpm, is is turning 2 to 3 times daily.
tnx.
Jim Burkes

Pond Boss had an article on the dangers of aerating old ponds which is now archived at BassReource.com here:

aerating old ponds

It's interesting reading if not an exact answer to your question. There are no timetables mentioned, but it does cover "sniff tests" to determine if you are stirring up the anaerobic waste products you want to eliminate to make the pond ready for fish. If your pond has never been stocked you won't have to worry about the fishkill aspects.

burger , what is your average depth?? If around 7 ft I believe your turn is closer to once per day, Im not sure where the 300-350,000 figure came from ??600 gpm is 864,000 per day (24 hr)Figure approx 325,000 gallon per acre ft @ .33 acres. 350,000 gallon in a 1/3 acre pond would be approx 3 ft average depth.Maybe Im looking at your post wrong as it has been a long day already. Ted

Bugermeister,

Ted is correct about the turnover rates. At 1/3 acre I am arriving at 3.5-4 foot average depth. You may have a hole that reached the 9 foot depth.

The concerns about aerating an older lake deal with the lifting of the hydrogen sulfide gases a byproduct of anarobic digestion. The sniff test is one of the easier ways and does not cost anything to see if you are lifting this gas into an otherwise healthy area of your pond.

If you DO smell the quoted "Rotten Egg" smell, you need to go through a start up period to allow that gas to be released a little each day.

Day one should be 15 min of run time, day two go to 30 min. Day three, 1 hour, Day four 2 hours and continue to add an hour until you are at 6 hours a day. Afterwords, you should be able to leave it on 24/7.

To answer your question about how long it will take to help reduce the muck in the bottom of the pond. The objective of the aeration system is to circulate the "bad" water and bring a healthy habitat to the bottom for the aquatic animals that will take care of that mess for you.

Therefore the timeline depends on how long it takes for their population to grow big enough to work on your debris. Fortunately you had enough forthought to do this before you ever had a big problem on your hands.

In my 15 years in aquatics, I have seen an aeration system start to do wonders within six months and take as long as two years.

A simple way to measure this is by using a piece of Acrylic pipe (3/4" will be fine) and screw a check valve on one end. Mark the pipe in 6" increments with a marker or I use red pin striping tape that I got at an auto parts store.

Push the end of the pipe without the check valve into your bottom soils until you hit what you may think feels like the hard pan. Bring the pipe up and measure. I would do this once a week and track it on a spread sheet.

To rinse the pipe out, unscrew the check valve and rinse in the lake.

If you have any questions, please do not hesitate to contact me.

Ted and Cary, thanks for quick and thorough response. I always know when the experts have posted, because the posts cease afterwards.
Ted, your numbers are correct, of course. I didnt think I was going to have to show that I was 'fluent' in math. Ha! The 300-350,000 was assuming slopes of banks, and that I was told that it loses lots of water in summer, hopefully largely due to the hundreds of tallow and sweet gum trees 2 to 4 inches in and around the pond. I have butchered hundreds in the shallow end so far. The transporation from the leaves must be tremendous. I also havent gotten an exact handle on size. After I finish clearing, I will walk a gps around it and 'map' it out. Anyway, throwing out false numbers brought out the experts. My plan!
350,000 I figure is a long term average; now I'm sure its more, as 8 inches of rain fell last wk. and pond is now overflowing. The 9 ft. depth of my 9 inch diffuser is actually in 11 ft. as of when I left Friday. The 600gpm was used as a low end ball park for a 9 inch membrane diffuser in a tip-proof 5 gal bucket, and about 1/2 way down inside the bucket. I saw your website about the vertex systems and just came up with a gpm that I felt safe with as a minimum.

The pond, at normal pool, is mostly 5 ft, with some very shallow, and 11-12 over abt. 20%.

Cary, that is very good advise with the probe for measuring the muck. Excuse my ignorance, but what is the check valve for? I dont think the pond is in an anaerobic or sludge/septic state.
Much of the shallow end drys out in late summer.
I want to stock, at least a few channels soon, so that by father-in-law can enjoy some fishing soon. He is 83. I can make a nursery in shallow water if necessary, and they are pretty tough, also I am American, you know, instant gratification! Any other advise welcomed. If my 600gpm is anywhere near correct, or low, then shouldnt I have at least 2 or 3 turnovers per day? Would more turnovers be beneficial? I'm in a hurry; I want to fish in it.

tnx for your time,Jim Burkes

Hello Jim,

I try to view these in the morning, but on nice mornings here in NC, I try to get my field work done then.

Your muck may not be any problems at all. I was just giving you an idea of a tool to measure for your tracking on how the aeration system is doing.

The check valve is to prevent any fluid escaping the pipe while lifting the pipe back out of the water. A lot of times you will be measuring "slurry" instead of a thick muck and it has the ability to slip right out of the pipe.

In a pond of yours a turnover rate of approximately 0.75 times per day should be sufficient. If there is heavy nutrient loading like found on Golf Courses or ponds that contain runoff from pasture land, then I would bump the turnover rate up to 1.3 times per day.

Other than waste water effluent ponds, pig, chicken, dairy ponds or intensive aquaculture ponds, a turnover rate of 1.3 times is more than enough.

There are some good questions and answers on my web page, www.aerationtechnologies.net

This is my first post, so please excuse any "flubs".
We have an approximately 3/4 acre pond that is about 18 years old and we are located in southern Illinois. We have a silt and muck problem. Pond was built "in a hole" and we had a lot of clay wash in for the first 3-4 years until we could get some grass and trees to hold onto the slope and stop the erosion. We also recieve ag run-off from grain farm next door. We get the run-off from about 5 acres of corn or soybeans. Also, have hardwoods (oak, hickory) bordering about 40% of the pond.
IN the shallow end, 6-8 feet from shore,we now (in midst of drought) have 12 inches of water and 2 feet of "muck". In the "deep" end, we now measure 9 1/2 feet of water. Factoring in the low water level due to drought, we have lost about 9 feet of depth.
We would desperately like to avoid draining or dredging. Is it realistic to hope that aeration plus removal of SOME of the muck (what a back hoe or track how might reach) will clean the pond out---- to clay bottom---within a few years? We've read the above posts, and quite a bit more. Where would we buy acrylic 3/4 inch pipe? Would Menard's or other home supply store carry this? What lengths does it come in?
Thanks in advance for any advice you can offer. We greatly appreciate Pond Boss for the ideas and experience it makes available.

Rabbit,

You mentioned that in the first 3-4 years you had the pond, alot of CLAY washed into the pond. Clay sediments and "muck", in my opinion, are two different beasts. I don't think anything other than draining and excavating is going to help the clay situation.
Muck on the other hand I equate with organic debris. Here you have some options. The benefit of aeration comes from the mixing of the water to limit stratification of a pond. (This topic has been discussed in the past. A search should yield numerous posts on the subject.) By mixing the water, the bottom of the pond now becomes more habitable for organisms that can act upon the "muck". Another interesting thread (or option) was started awhile back which involves using septic tank additives (bacteria) to combat muck buildup. The jury is still out on this concept but its worth reading.

Hope this helps. Welcome to Pond Boss

Russ

Russ, the experts say, and it is happening with my pond, that muck/organic debris is being consumed by natural and added beneficial bacteria due to getting O2 to the bottom to feed the bacteria. I have read articles that a pond can double its depth with a couple of years of bottom aeration, assuming it is muck, as mine, many years of decomposition of leaves.

BM,

You may not have been around here when an article was referenced (dang, can't find it) that said Egypt used Tilapia in the lake formed by the Aswan dam to reduce sludge/muck and add to the bottom depth 2 to 3 inches per year. Imagine the amount of material that must be...2 to 3 inches off of a huge lake bottom.

I can say from personal experience, I've seen them do it in my ponds...like a vacuum cleaner.

I know many folks prefer a chemical solution and I do not, but maybe a combo approach would work. Something to consider.

Meadow, I remember seeing your post, and will probably give it a whirl next spring. Thanks for the post.

Burgermeister,

I concur. Perhaps my initial post was misleading so I edited out the comment that aeration, in itself, does little for muck removal.

I know a Bill Cody post has explained this concept much better than my feeble attempt but unfortunately i'm suffering from Meadowlark disease and can't find the post.

Russ