windmill aerator for a pond.

[oakiemac]

Does anyone have experience using a windmill to aerate their pond. I found a company that sells 10, 12, and 16 foot windmills that put out 1scfm to aerate ponds. My pond is several hundred yards form the house so I would need something like this. The only draw back that I can see is the price. They cost $600-700. Any comments would be appreciated.

 

[Dobber30052]

I suggest you head over to "Pond Boss" @ http://www.pondboss.com/cgibin/ubbcgi/ultimatebb.cgi . It's a great little mag, and the folks on the site are pretty helpful, there are several threads and links about aerators. Good Luck!

 

[Gary_in_Indiana]

A 16' working windmill brand new for $700 sounds like a bargain to me.

 

[rmorgan]

Unless you have steady winds, windmill aerators are a dicey solution to pond stagnation and stratification. The times you need aeration the most are mid-summer. Here, at least, that is when the winds are lowest. Same with early morning. If you happen to live where it's reliably windy, they are a good solution. Otherwise, they will be an attractive way to watch your pond turn over and kill your fish.

 

[fishman]

Oakiemac,

I second the concerns with the windmill aeration system. It requires basically hurricane-force (well, not really. 30 mph though) winds to barely approach the very lowest end of an electric aeration system. The majority of fish kills occur in the dog-days of summer when there is no wind. That is, unless you are in the frigid Northland and have problems with ice.

If you have electricity within 2000 feet of your pond, you can use an electric aerator. The system I spec is rated for a tubing run of that length. Much cheaper than an electric line.

Additionally, you can get a much more capable system for just a little bit more money (because of the extra tubing). For those with electrical nearby, the cost is similar. Electric costs run a maximum of $20/month, and usually less. This is for a system capable of aerating up to a 1.5 acre lake, depending on depth.

 

[rdln]

I have considered a windmill deal for mine too because of the distance but never thought of running the airline instead of the electric line. interesting! can you get more explicit on specs? I have about a 3/4 acre pond whose center is about 900ft from electric.

 

[fishman]

Rdln,

The effectiveness of any aeration system is determined by the maximum depth of the pond and its shape. Round, deep ponds are the easiest and cheapest to aerate, because fewer diffusers are needed (one in the case of smaller ponds) and the oxygen transfer efficiency and mixing is more efficient.

For example, if your 3/4 acre pond is roundish in shape, with a maximum depth of at least 10', your pond would only require a 1/3 hp compressor and one diffuser.

There are systems capable of aerating up to a 20-acre lake available for a lot less than most would expect. The equipment and electricity required to pump air is a lot cheaper than that required to pump water (as in a fountain). It also works much better.

If anyone wants more information they can e-mail me or send a private message.

 

[rmorgan]

To expand on Fishman's point, I have a 1/3-HP compressor with a bottom diffuser, 3/4 surface ac., max depth 12'. It seems to do fine, although I do think it costs more to run than $20/mo if it runs all the time. I run it 2 hours morning and evening for three seasons, and have gone to 4 hours morning and evening for the summer months. For reasons I don't understand but Fishman can probably explain, a shallower pond requires more aeration for the same surface footage than a deeper pond. The compressor is more expensive and less aesthetically pleasing than the windmill, but I know that it is going to come on when the timer clicks.

 

[oakiemac]

Thanks for all the replys. I think a windmill would look very nice on the tall pararie grass and wildflowers that I have planted around the pond but if it takes 30mph wind to do any good then I'll have to think about running some tubing. I guess this brings up the question of do I really need an aeration system at all? My pond is small (100'X80') and it is fairly shallow being only 7' deep at the deepest. When the pond was first put in, I pounded down a well point for watering the garden and I also send it to the pond where it comes down a 5' rocky waterfall. I did this to add cold water in the summer, for aesthetics, and to help aerate. There seems to be a lot of Hydrilla growing on the pond bottom and alge is starting to grow around the edges. Is the waterfall enough or should I invest in an aeration system? Thanks again.

 

[rmorgan]

Oakie--fish are the determining factor, I think. If you don't want them, you probably don't need to aerate, and/or the windmill aerator would probably be fine. If you want to maintain a fish habitat, then you probably do need to aerate. The risk is that with hot weather, the water becomes severely stratified, with the hot water on top preventing the cold water on the bottom from having any contact with oxygen; vegetation in the lower strata dies, depletes oxygen, then a rainstorm mixes the water, dilutes the oxygen in the top stratum, and fish are killed. This is called "turn over." Vegetation is relatively irrelevant to an aeration decision, except that as vegetation dies and decomposes it deprives the pond of dissolved oxygen and makes it less hospitable to fish. Similarly, aeration will have little or no impact on the hydrilla or algae. The waterfall is negligible as a source of subsurface oxygen. Here is a link to an article which discusses this stuff. http://agpublications.tamu.edu/pubs/efish/370fs.pdf