Pond Boss Forums AERATION Systems questions How deep ?

Recently purchased property in central Wisconsin that has a 100 X 300 foot pond. The pond runs to about 8 feet deep but a good part of it (50%) is only 4 to 5 feet deep. It does not seem to have fish and I want to introduce either bluegill and or bass and or catfish. I have a limited budget so deepening the pond and aerating it might be too much. What would be the better and or more economical approach assuming that I would need to deepen it by about 1000 cubic yards.

David,

I tried looking up the minimum depth in pub 590 and it looks like 8 to 10 feet is recommended for your area.

By far the cheapest way to add depth is to raise the dam height, assuming it is an embankment pond.

It is not only far cheaper, but it also does not require pumping out the existing pond and killing the occupants.

If you have a suitable location, raise the dam to the height you need for the additional depth.

thanks but it is not that type of pond. Its in an area with a high water table so the prior owners simply dug a hole and it filled with water. I have read the publications for this area and most recommend that a fish pond have a minimum depth of 10 to 12 feet but I have also read that some area fish ponds do well with 7 foot depths. This has been a drought year and the pond is only down about a foot and rainfall is about 10 inches less than what is normal.

David, I would think you could live with your 7-8 ft and shallower areas in your cooler climate. You are close to .7 acre and as long as you keep with warm water fish and dont over load it I would consider using what I have. Also do a muck depth check and realize that when you aerate properly you will gain some additional depth with the aerobic bacteria consuming the bottom organic sediments (not to be confused with soil that may have washed in over the years)Very feasible to loose 3-4 inches per year of organic muck. This may gain you some depth over time.It would be nice to drain and redo or raise the bank as mentioned but when these are not options just look at what you have in a different light. Good Luck

Thanks for the suggestions. This is a great site and the members seem to be a cut above the guys that post on other discussion forum type sites. Does seem that most of the guys are more southern than northern. test
http://www.weather.com/activities/recrea...WI0003&clocid2=
As I said the pond is a hole in the ground and the water fills it to the normal water level. I don't have a dam and raising the bank wouldn't seem to do anything. One biologist gave it a quick look and said that I ran the risk of the fish suffering winter kill due to being too cold not from any oxygen deficiencies.
Ted your muck test is that just probing the bottom ? Also when you stated

"dont over load it I would consider using what I have."

What is it that you have ?

Here is a picture of the pond...note that it has a lot of birch and pine near the shore line.
http://wildwacky.blogspot.com/2005/11/pond-pics.html

I think Ted was suggesting that you utilize the pond with the depth you have, but don't overload the pond with too many fish.

With all the trees around your pond I'm sure you have alot of muck buildup from leaf litter. As Ted said, aeration can help get rid of the organic muck & prevent it from reoccuring by oxygenating the lower levels of the pond.

Dave, Ric is correct on my comment that a normal stocking rate may be an "overload.When you stock it consider a 25-30% rate to start. There are many many ponds just like yours that are great little fisheries.My smallest pond is only 4/10 acre and has some 3-4 ft depth at the water source entry point(approx 20-25% this depth) and is a very nice pond.Started with 12-18 inches of muck 5 years ago and have none as of today. It is circulated with 4 diffusers due to the 38 acres of ag watershed that feeds it. It is the pond on the right side of the aerial pic on our web page.As far as winterkill from being too cold I wouldnt worry about that, as soon as you have ice cover the bottom of your pond will be for the most part the same temp as the rest of the ponds in the country with ice cover..Now as far as o2 depletion that can be different. This pond may be a candidate for a central diffuser(or 2) in the deeper area and a additional diffuser designed and placed in the shallow for additional spring summer and fall application but primarily a winter diffuser. This approach keeps the deeper water warmer in the winter as the main diffuser is shut down and all of the cfm is diverted to the shallow winter diffuser.I would also plan on running the winter diffuser most of the winter "if" you do a muck check and have 6-12 or more inches.This will allow the pond to ice over which is good (insulation) and open somewhat to let gasses out and sunlight in if snow cover persists on the ice. Like Ric stated with the tree debris you have a buildup that robs the pond of oxygen is probaby there.Decomposition takes place 24/7 >365 If you have decent dissolved oxygen then the aerobic bacteria will decompose and render your sediments to CO2 and H2O if not Anerobic bacteria will do a lousy job of decomposition and leave you with sulfur foul smelling muck. Your biological (biochemical)oxygen demand (BOD) is high and the supply is probably very low.You want just the reverse of this. If you add fish your demand is even higher so a need to address this is vital to a good fishery.This will reverse in time when you aerate.I would not consider stocking it until I had a plan to address the low O2 situation.When you do a muck check just use a rod or pole of any type that is 1 inch and covered on the end. That size snakes through muck quite easily and you will feel the resistance to the hard bottom.Once you start to feel the pole enter the muck just mark the water line and see how far down you can push.Crude but it works. I believe Bill Cody had a post on muck depth check awhile back so you may want to do a search for that. Also just stir it in the 2-3 ft depth from shore and if you can smell it dont stock it (just yet)Ted

Thanks again to you guys for your help. I will do that muck check thing and see what I get. Funny I had called a guy who actually pumps out pond muck he works in the area of my pond and has a web site the name of which escapes me but is easy to find with a search. In any event I finally got thru to him about a couple of months ago and he shot me a quote of $7,000 (2 days work )to get the muck out of the pond. He did that by asking 2 questions...how old is the pond and how big and deep is it? In fairness I had asked for a rough estimate so I got what I asked for. After getting that rough estimate I started looking into aeration. Incidently business for that guy is so good he wouldnt be able to see me until next July and it was this July when I was talking to him...he is running 2 shifts... makes you wonder.
Another funny thing is while poking around yesterday I called an excavator out of the yellow pages and it turns out it is the same guy that dug the pond some 20 years ago ! He sounds like a real good guy and I am meeting him this weekend. So I will listen to what he says. he already explained that the prior owner just wanted a bird pond as he was an avid duck hunter. He said to me while talking OK we'll putta hole in thar for ya. he said it in a matter of fact way that gave me a good feeling. Maybe I can aerate and deepen.

David, keep us posted. Good Luck !!

Thanks Ted for all your advise. Whats your take on these linear aerators like the Alita Model AL-80 ?? I have searched the forums here and didnt really find much commenting on them. I know they apparently are quiet and the cfm seems pretty good but they dont seem to be very popular.
I will keep you posted on my next moves etc.

DavidB: you're right that the more southerly folks dominate on this forum. However, there is increasing interest from northern pondmeisters as well. You'll occasionally hear about walleyes, yellow perch, and smallmouth bass, as well as the more traditional largemouth bass and bluegill. :-) Keep posting, and you'll get good information from good folks like Ted.

Dave...I hear you. As I have progressed here some of my fav posts have been about the yellow perch as pond fish. Like most I love the yellow perch and where I was only thinking blue gill or large mouth with some fatheads am now turning towards blue gill, yellow perch and fathead.
This is a fun spot.
if I can get my 8 foot deep pond increased to say 12 to 15 or aerate with say a 10 foot deep pond then seems I can have the perch. I like to think of them as mini walleyes

I tend to think of their fillets as mini-walleye fillets, as well. :-)

David,Good question. One of the reasons the linear pumps are not that popular is the depth at which they operate.The AL Alita-80 for example has a suggested operating range of .05-.25 bar or 3.5 psi being .25 bar. Figure that each 1 ft of water depth that you place your diffuser in will have 1/2 lb of back pressure to overcome the downward force of the water. 12 ft equals 6 psi backpressue plus nothing calculated for line loss due to length and friction depending on hose ID.So if we use this pump at 6psi the cfm drop to approx 1.5 or 37% of the free flow.We are now way over the suggested operating range and will shorten pump life.This would be an expensive way to get 1.5 cfm. Your pond could take approx 3.5-4.5 cfm depending on where you set your goals and your stocking rate.Linear pumps are very good pumps for shallow ponds or water garden situations.Most rotary vanes (exception high pressure models) are limited to 10psi but that is 18-20 ft of water depth. Again not taking into consideration line loss due to total hose lengths. Piston pumps are now very popular since they are very price competitive to rotary vanes. The advantage of a piston is the ability to operate in water to 30-35 ft depth and very very long tubing runs for pond and lake sites that do not have electric power near by. An example of this is a 16 psi model Thomas WOB-L pump that has diffusers in 12 ft of water could have the pump located 7300 ft (1.38 miles)away and still be within the operating psi range of 15.9psi When a piston pump is located pond side or has short tubing runs of less than 1000ft it will run in that 6 psi range or 12-14 ft of water and runs very cool.This is why sizing a system includes knowing the desired turnover rate of the pond the depths,configuration and what the tested rates at different depths and cfm levels of the diffusers are.Ted

Thanks Ted for that detailed explanation. I see your site has a number to call for aerator sizing help so that is something I'll do after (if) any additional digging is done. Hopefully I can get some additional depth and then start aerating next spring...guess I will need to be somewhat patient...probably get some fatheads in there soon and wait to see how they do.
A few years back I owned a 40 acre "pond". The fishing was exceptioal, crappie, bluegill, LMB, perch etc. etc.and all good size except the crappie were all the same size, about a pound...never figured that out. Even had a few tiger muskie stocked. Lived about 250 miles away and the locals fished the pond out while I was away. It was easy to get on to the pond from the public road. I sold when the locals would be out on the pond even into the after midnight hours.My wife and I could hear them from inside the cabin. This one is a lot smaller and difficult to access so I dont think I will have that problem. Thanks again.

After meeting the excavator over 3 weeks ago and calling him 2 times to follow up and again today he shot me an off the top of his head quote for $3,500...thats to dig out 750 cubic yards or push it out. According to him the bottom is sand not clay and there are springs down there.
I am not very confident dealing with this guy and being 230 miles away doesnt help.
At this stage I am tempted to do my deepening project myself. Rent a pump, pump out about 4 feet of water then get a bobcat and have at it.
Seems like it might be fun.
On the other hand I have no experiance with this type of work and wonder about timing and weather. This is Wisconsin and its now December and ice is probably already an inch thick. Wouldnt seem I could get to it until early spring...if there is one...late march or April but that could be real sloppy.

Just thinking out loud.

http://photos1.blogger.com/blogger/6626/1290/1600/Picture.jpg
slowly and hopefully surely. added the 1/4 hp rocking piston model and intend to supplement it with a linear at the shallow end which i would leave on thru the winter. This is going to be a long drawn out procedure and while fun it is frustrating to be 200 plus miles away and that fact, in and of itself, probably enhances my strong desire to get the pond fishable.
Have given up trying to find an excavator that is both willing and able to deepen the pond. Thanks to the experts here and reading thru all the posts have basically decided to have this be a fathead/perch pond with maybe a northern in there to keep the perch honest, perhaps a LMB or even a SMB or 3