Pond Boss Forums AERATION Systems questions I would like to aerate my 3/4 acre pond

Hello I just joined this forum today because I have been reading posts here about building an aeration system. I have a pond in front of my house in southern Illinois which is 3/4 of an acre. It is oblong shaped about 100 yards from end to end and widest about 200 ft at the dam. It is about 18' deep out in the middle maybe 50 ft from the dam. The pond is about 20 years old dug in the mid 90s. It is stocked with channel catfish and largemouth bass also has a lot of bluegill. I keep it clear of algae in the summer using copper sulfate about once a month from about June thru September.

The reason I'm considering aeration is last September there was an algae bloom which killed a couple dozen of my largest fish catfish and bass but also about 3 grass carp that were over 3 feet long. I replaced the grass carp but I'm concerned it will happen again. I think I caused it by introducing 7 or 8 muscovy ducks to the pond last summer. We raise the ducks for meat and I'd like to try to make it work with them although I realize it may be taxing the system. I was wondering if I could solve a couple issues with aeration protecting the fish and also keeping an area of open water in winter for the ducks to escape predation when it freezes over. I also wouldn't mind getting the water temperature more uniform by bringing some of the cold bottom water to the surface where we swim.

Well I don't have the budget at the moment to buy a nice system that seems to cost hundreds of dollars plus so I would like to try piecing something together a DIY model. I was look at vacuum pumps on ebay... would something like a 1/3 HP Thomas 2660 pump work for my size and depth? Any advice is appreciated. Thanks I've already learned a lot here.

Welcome to the forum, jcgoldie!!!

Consider it a blessing the grass carp died...they are lazy and eat almost nothing at that size.

Aeration, properly sized and designed is almost always a help, and can be a DIY project. A 1/4HP pump with about 4CFM on the pressure side should be plenty for your pond. Even a "cheap" DIY system that functions properly, and is reliable, will cost several hundred $$. Aeration, unless you educate yourself VERY well, is not one of those things you save money on in the long run, DIY.

You said you treat your FA (Filamentous Algae) with copper, but that can also reduce the DO (Dissolved Oxygen) in the water...both as the algae decomposes, and the lost O2 it makes every day.

Is it possible some of the "large fish" were just old? A couple dozen large fish, that are also at the end of their life-span is not a huge surprise in a lowered DO situation. If you had 50-60 dead fish in several size classes, THEN I'd worry more...

I'd suggest reducing your biomass over aeration with a lower quality aeration system and lower budget. It's a WHOLE lot more fun catching as many catfish 1.5 pounds and up as you can, but catch about 50 pounds of LMB under 14" long (Large Mouth Bass) first...If not wanting to eat the smaller LMB, cut a gill and toss it back in the pond to fatten the catfish before deep frying them!!

Well I kinda agree with this? I guess it all depends on how much you can spend on a system? When you say you cant afford 100's of dollars what do you mean? 5, 6 7 hundred or more? I guess what can you afford we need to know first?

I have a 1 acre pond and had a 350 to 400 dollar system for about 4 years and it worked great, but my pond is not 18 feet deep so like said above you would need a decent pump that could pump to 20 feet. I would then put the pump in about 15 or so feet so like Mr. Bill Cody says you don't want to run your pump at it's max depth all the time it will wear out quicker and not last as long that way. Or you want a pump that can easily handle 25 or so foot depths.

I now have a GAST 0325 1/3 hp pump and it's sweet! I got it used for about 140.00. Keep in mind though you will need a lot of other stuff.

Let make a quick list and figure a bit high from what I have.

1. A decent used pump to pump to at least 20 feet. $200.00

2. Weighted 5/8 in ID hose to go from pump to air station in pond. This really depends on how far your going and the gong rate per foot. I went 85 feet it costs me about $120.00 bucks at the time.

3. You have to make up a air station base or buy one. You need at least to air diffusers for your size pond. I run 2, 9 inch fusers in my 1 acre pond and it does fine. This was cheep for me cause I made my base out of a side of a computer case and used PVC to make my spouts for my fusers. So a 2 air diffuser station could cost you anywhere from 50 bucks to 150 bucks depending...

4. What ever your going to put it in if you are.....

5. Misc... clamps, valves, and stuff like pvc glue 30.00 bucks.

So give or take some as we figured a little high on a used pump I think..... 400 to 500 bucks. Like I said it all depends on what your willing to spend or can spend, but either way it will cost you some 100's....

RC

Thanks for the welcome and this is good info. I'm a little unclear on how I can be sure the pump I buy will reach the depth I need with adequate pressure. The one I'm looking at on ebay is Thomas 1/3 HP 2660CE32 3-4 CFM refurbished for $120. I take it from Rainman's reply this would be big enough, but after reading yours, maybe not? I'd be running it off my swim dock and the deepest part of the lake is about 100 ft from there... I was also unsure what size weighted hose I'd need, I take from your post 5/8" would be necessary? Also when you say 2 air diffusers you mean 2 of the 9" membrane discs? I can make the base no problem.

Yes I believe that pump would work if it doesn't push real good at 18 feet put it at 15 feet. Your water will still mix for the most part. Maybe Mr. Cody will chime in on this. He and Rainman know their stuff I'm just a rookie but it can be done for around 4 to 5 hundred bucks like RM said if you do your homework.

Yes 5/8ths inch weighted hose is the way to go IMO. Once it's in it's in I haven't done anything to mine in 5 years and never have to worry about it.

Yes 2 air diffusers mean 2, 9 inch fine bubble discs vertex are some of the better disc you can get. Here are a few pics of my first setup. Keep in mind this pump was my first pump and it worked for me for 4 years but I only had it in 7 to 8 foot of water, it will NOT work in your situation, but it will give you an idea of what I did. I originally setup 3 air fusers and now have the middle one capped off as I felt I really did not need it for my size and shape of pond.

The Thomas pump with 3-4 cfm should work providing the psi is above 30. Used pumps will work for aeration although life span will vary from pump to pump depending on prior use and how long you run it each year. I've seen some last 1 year and some 4 yrs & still working. Motor bearings and pump mechanisms have a life span. The pump will be the most expensive item of the DIY aeration system.

Get a good air filter for the pump and keep the filter clean (annual check). Air filters can be homemade. Although not imperative, I like a pressure gauge and a pressure relief valve on the pump. Air outlet manifold can be simple and homemade with metal plumbing parts (galvanized).

Airline can be cheap black polyethylene irrigation pipe (1/2" true ID 5/8" $12/100ft) or kink proof garden hose. Be aware these cheaper hoses need added weight to sink them (1/2lb per ft) and care should be taken not to kink the hose then hose repairs are needed. Air line does not have to lie on the bottom. One of my demonstration airlines floats until it gets to the diffuser.

A good quality coiled hose or tube diffuser can be homemade for about $15-$25 including a check valve. My first diffusers back in the 1980's were homemade. Send me a PM for ideas to build a diffuser.

JC,

There you go your got a lot of options in front of you. Bill helped me get my gast 0325 working good as far as filters and relief valve and a nice gauge at very little cost. He is the guy I would recommend you working with in a heart beat. He knows his stuff and won't do you wrong.


Good Luck and keep us posted as to what you do, would love to see some pics of your quest for air when you start working it!!

RC

Thanks a lot to everyone who responded here, you guys know your stuff. I went with the used pump but spent a little money on the weighted air line because was worried about swimmers and fishing hooks getting caught up in it if its not on the bottom. I also bought the recommended vertex diffusers.

Here's the pump I got which has been rebuilt so I hope that extends the life of it which Bill warned about. It also is mounted to a plastic frame and plug and play ready also with an extra cooling fan which appealed to me:

Thomas pump

So my investment so far:

Thomas pump ebay: $120
100 ft airmax 5/8 weighted hose ebay: $160
2 vertex 9" diffusers: $43 ea

$366 total

I figure I'll spend maybe $15 on connectors I already have some pvc stuff.

I have an old deck box so I'm going to mount the pump in that on my dock. I hope that provides enough air flow. I also was thinking I'll connect the 2 diffusers with a piece of PVC going through a 5 gallon bucket about half way up and fill it about half full of concrete with maybe a couple of 2x4s on the bottom in an X so it can't tip over. I don't want it so heavy I can't move it for winter.

Lastly I'd like to know if these locations look like a good place to start. Here's my little lake:



The narrow end of the lake gets very shallow on the end with the cypress trees at the top of the photo. I was going to place the air station there where its 4 or 5 feet deep in winter. The mark out in the middle is maybe 16-18' deep for summer. Does this look like it might work?

Thanks!

Rainman I have another question. I see from your profile you live in St.Louis and you advertise stocking tilapia. How do you keep them alive through the winter at this latitude? I live about 30 min north of STL near Alton, IL. I have a second lake a little bigger at the back of my property its surrounded by woods without much airflow gets covered by watermeal every summer. I just use it for water for the cows. I put grass carp in there few years ago didn't help. I did some research found tilapia is basically the only thing that would eat that watermeal. But I also assumed they'd all die off in the winter so wasn't worth the investment. Was I wrong about that?

Tilapia dying each fall is part of how they become such a great management tool. Tilapia are illegal to stock in an open system (Weather exposed water).

Wasn't worth the investment? You buy copper to pour on algae for about 4-6 weeks before it recycles and starts again. Tilapia eat the algae, then get eaten by other fish, improve DO levels in ponds, and can up to quadruple the fish biomass a pond can sustain "naturally", (not including weight of the tilapia)....all for about the same money spent on copper products.

Either way, Illinois and Missouri DNR's are run by idiots that are 50 years behind on fisheries biology.

The southern diffuser location looks good, if that is the deep spot...northern diffuser, I would move south, just north of your dock and centered east to west.

Interesting. I would estimate I spend about $200-250/ yr on copper at the feed store ($100/50 lbs) Would that buy enough tilapia to clean a 2 acre lake of watermeal? (I mean hypothetically of course if it were legal.)

I agree with Rainman, move the north diffuser more towards the corner of the dock - centered between the sides. The annual copper accumulation in the bottom is bad for the pond's sediment ecology. Carbonate bound copper is a heavy metal and does not decompose. High concentrations from repetitive use eventually becomes problematic.

Thanks again both of you I will take some pics when I get the system together. Do you think this will move enough water from the bottom to keep an area of open water throughout an average St.Louis winter? I didn't realize that about the copper. I am hoping between the muscovies (not sure if they will help or hurt with the added nitrogen) and the aeration I won't have to use so much this year. I was scared to use any sort of herbicide because as you see there are some very nice cypress tress rooted in the water on one end of the lake and I don't want to poison them although I assume copper can't be too healthy there either.

Bill, RC51 mentioned you helped him find a gauge for his pump, may I ask also what you recommend?

jc, our winters are fairly mild....move one diffuser to about 4' deep and it will keep a huge area open all winter, and shouldn't supercool the water (which can kill fish also)

As for Tilapia, I'd rather not discuss a hypothetical, Federal Felony.

Welcome from another STL area IL guy. I am not to far from you if your in the alton area, I am just outside of Bunker Hill.

Here is a thread on my aeration system that I put together last year with a lot of help from Bill Cody. So far it has worked well for me and the only issue I have had is my check valve on my manifold is stuck open right now.

Hi Blue72camaro we are probably closer than you thought, I'm at the south end of Blueridge rd. Thanks for the thread link I learned a lot looking at your pics. Did the system do what you wanted it to do last year?

So we have a nice boil I think. Here's a couple pics... everything seems to be working as it should. Thanks everyone for the help!

I love the design. I know my 'boil' is bigger (more spread out) when the water above the diffuser is deeper and almost no boil when the water levels drop.

I'm now wondering when I look at your design if I would get a better boil (meaning more air bubbles lifting water) if I separated the distance between the diffuser disks. Since mine is a premade option from Vertex, the diffusers are close together. If I made my own base and spread them out like you did, I wonder if the 2 separated plumes would move more water than 2 plumes so closely placed together that they essentially merge or overlap as the column moves up?

The folks from Vertex should know the optimum placement between disks when they designed theirs right?

Canyon the answer to your question is NO!! It would not be better. Actually your supposed to have your fusers as close together as you can that will give you your best upwelling of water into the water column that little piece of info came straight from Mr. Bill Cody himself so I KNOW it's right!!!

JC actually has his to far apart.... it works but not as effective as being about an inch apart....


RC

Correct. They did testing and that's what they came up with. I believe they found that there was a sweet spot for diffuser disc placement with regards to how far each disc should be placed to each other, and that is what their diffuser assemblies are based on.