Pond Boss Forums AERATION Should I aerate? Winter aeration

I live in central Illinois and have a 1.5 acre pond with 2 diffusers. I had heard somewhere that I should turn off the one in the deep end and leave the other going all winter. Is this correct? At what point do I do this?
I have searched the forum but can't seem to find anything pertaining to winter aeration.

Thanks
Tom

If the two diffusers are at equa-distance in the deepest water of the pond I would use neither one in their present position and depth. Either bring one up close to shore in only about three or four feet of water, or run anorher airline and diffuser into three or four feet of water to your compressor. I've also heard of suspending a diffuser a few feet below the surface.

Personally i actually not only run a separate airline and diffuser to shallow water, I change out my 4 cfm compressor to a smaller 0.8 cfm compressor.

What you are trying to prevent is super chilling your entire water column but stll leave some water open to allow light in for photosynthesis that produces oxygen. Deep snow and no photosynthesis not only does not produce oxygen, it can kill the plants and then they use up D.O. By their decomposition.

A fertile frozen over pond with no open water covered by several inches of snow or more has a finite amount of days until it's in trouble. Decomposing plants that are not only not producing oxygen but are using it up via decomposition only exasberate the problem.

Thanks Cecil,
That's pretty much what I figured but I am new to pond ownership. One of the diffusers is already in the shallow end (about 4') so i will leave that one going.
Another question...
If I close the valve down a little on the one left running, will it put too much load on the pump?

I would bleed off some extra air by disconnecting the hose for the one not in use. You'll have to do some adjusting with the valves as all the air will want to go to the open one.

Another option is to let all the air travel to the shallow diffuser which will make a larger open water hole in the ice. IMO larger open water is better than smaller in ice and snow cover.

Here is link to another discussion about potential winter kill under the ice and snow:
http://forums.pondboss.com/ubbthreads.php?ubb=showflat&Main=28519&Number=365263#Post365263

Bill, with your option I agree on having more open water, but could it not depend on the type of diffuser being used and how much pressure it could handle?

I know I've bled air as Cecil suggests when I've had only one vertex diffuser open as I was under the impression I could damage the membrane.

Just a thought

What are these membranes rated for cfm? I know they blow up like a basket ball when no water pressure on them.

Cheers Don.

If you do a Google search for the brand you have the mfg. should have the specs available.

For example, here is the diffuser I am using

A single will handle 1.4-4.2 cfm, double will be double that for this particular diffuser. You should be able to find the same type info for your particular unit.

Keep in mind, your pump output will vary with the depth of water. Some pumps a lot (linear air pumps), others not so much (rocking piston or vane) depending on design. Your pump should have a performance curve also to tell you the output at a given back pressure (depth).

Dono A Vertex single disc (Generation 3)is a min of .5 cfm and a max of 2.5, however at .5 they will need more flexing and at 2.5 you will stretch the membrane over time but they will operate in this range.Middle of the range is best for all rubber membranes.

The fish farm near me and numerous other aeration "specialists" sell lots of single 9" disk unit diffusers with a 1/4 hp rotary vane compressor. Many of the 9" disks have a normal operation cfm of 0-3cfm and max of 5 cfm. Right or wrong - the disks are probably getting somewhat over stretched with only one disk per compressor at 3-4cfm per disk. Over stretching a membrane no doubt shortens its life span.

DonoBBD, if you can find a spec curve for your pump, like the following example, and know the depth of the diffuser, then you will have a better idea of the cfm lost at depth. This is a graph of a linear diaphragm pump which looses volume very quickly at depth. Likely whatever you are using, not nearly as much.

Linear diaphragm pump

The legend across the bottom is depth of water in feet.

This may skew the subject matter a bit. Is a compressor and a single diffuser capable of moving enough water to keep an open area in a pond with 24-30 inches of ice? Wouldn't a circulator do a much better job under those conditions?

Dwight, I'll cut a hole in the pond tomorrow and let you know.

"Wouldn't a circulator do a much better job under those conditions?" Good question if one has thick ice. I think most circulators have bigger hp motors compared to the standard 1/4-1/3 hp air compressor. It would be interesting to see a comparison of the two methods.

I do know once the ice is thick enough it's tough to get the upwelling water to cut it. Don't ask me how I know.

I didn't have too many issues with the big pond installing a diffuser and keeping water open after the ice formed, as I think there is relatively more warmer water reserve in the depths. Also the hole started out big enough for the wind to aid in keeping it open.

Different story in the smaller trout pond that is more protected from the wind and freezes sooner and deeper.

Going to blow snow off the trout pond today at least in strips like below. The hard part will be to get the snow blower back there through 3 foot + snow drifts!

hello all Derek here been sitting here in north canton ohio looking and fearing is the hole in my pond to big or to small.120ftx80ft avg depth 10ft. im thinking if temp is -0 as it has been here repetedly abig hole would not be a good thing? or am i thinking wrong.

Derek, what do you consider big?

Here's pictures of my pond taken a short while ago.

So much snow that the floating dock is barely visible.


Here's a closer picture of the open hole from the diffuser. It's in approximately 10' of water, but the diffuser is about 3' beneath the surface. It's a single membrane diffuser. I am running about 3.5 psi of air to it, and bleeding off extra air from the compressor so I don't blow the membrane.


A picture with a wider view. I'd say the open water is about 30' to 40' diameter. The platform that the feeder is sitting on is 12' wide.


I drilled a hole in the ice right by the floating dock. There is about 10" of snow on top of the ice, about 3" of water/slush, and 13" of ice.

I blew most of the snow off my trout pond today with the snow blower. Was going to blow snow off in strips on the big pond but ran out of time. Found water under the deepest snow next to shore on the trout pond.

Who knows, maybe I'm just allowing the ice to get thicker!

Scott,

is your diffuser under a float or attached to the pier? Is it attached to the duck decoy you use the rest of the year?

Edit: Looks like it's not near the pier.

It's a single membrane diffuser that is attached to a weight in front of the feeder. When the diffuser is working, it floats up off the bottom to the length of the rope. When it's off, it sinks back down and doesn't interfere with summertime fishing.

If you go to Google Earth, look at the latest image. It has the pier in it.

Scott,

I've never heard of them being anchored off the bottom. Is that an original idea or am I just out of the loop?

Cecil, something I thought up. Single membrane will float to the surface with the Vertex bottom line tubing attached (tested it first) and I needed a winter diffuser. But, I didn't want to keep pulling it in and out every year. I also wanted open water in front of the feeder so I could feed all winter long. Mission accomplished. When air isn't running in it (i.e. summertime) it is laying on the bottom and not in the way of fishing. I used either 1/4" or 3/8" braided nylon rope to set the depth. If the pond is at full pool it's about 1/3 the total pond depth. If the water drops, then it's less, but there is less total depth in the pond at the same time. That was the easiest way that I could figure out how to regulate the depth of the diffuser in regards to total pond depth for the winter with minimal work on my part.

Very clever! I knew they floated as I had one float up once when the bricks came loose.

Wow Esshup,that some thinking out of the box there.Think ill try that next year.I have two dual 9"in my pond one in the deep end and the other in the other side that I pull in for winter by walking to the end of the dock and using a 20' painting pole with a paint roller for a hook to fish out the line and drag it close to shore. Cecil my hole is about 6 to 8 foot. Just got a little nervous when it was below zero for days,and it was down to two feet.Bleeding off way more than half the air that I have.Going in to the negative temp here again in the up comming days.maybe i should make the hole bigger. Thanks for the pics.darn I love this site, have learned so much from all you Wise folks.