Pond Boss Forums AERATION Systems questions Pump question

I've posted about my 1/4 acre pond for which the initial construction was completed a couple months ago. (This is a swimming/fishing pond: I’ll have FHM/GSH/SBS/RES/HSB.) Waited to see if the clay would hold but determined it wouldn't, so we installed a robust pond liner from BTL and now while it takes its time filling, we're taking care of all the other sundry projects involved.

My contractor (plenty of experience with ponds) is suggesting a pump setup (out of water) from The Pond Guy which has the specs he's looking for:

* 72’ head pressure * 11,000 GPH * flow rate 65 DSI * 2 hp * 230 volts * 1.5” input/output outlets

* 5- year warranty

He estimates pond will have ~972K gallons of water when full, and that this pump working at 11,000 GPH will take approximately 88 hours to turn the water over completely.

The pump is offered at ~$1400, which…..seems a little high? I also confess that when I was shopping for the pond liner, The Pond Guy wanted $14K(!) for basically similar specs to the one I eventually got from BTL for $7K. So….perhaps they tend to be on the high side on big-ticket items like this…?

Anyway, I'd like to get some feedback/suggestions from people here, and hopefully, a less expensive option as I found w/the pond liner. NOT interested in going on the cheap; the aeration system and everything related to it is not an area where I intend to nickel-and-dime it. Fwiw: my contractor also says that a pump like this would be fairly simple to rebuild at some point if necessary, which is a plus.

Thanks for any of your usual wisdom.

We would like some more background information.
1. Pond depth?

2. Should we assume the aeration system is a water pump and not an air compressor? Why water pump and not air compressor>

3. What is the set-up plans for the pump? Depth of Intake? Fountain arrangement?

4. Link to the pump system from ?

What is your KWH cost there?

I know where Bill is going. For aeration and not aesthetics, I'd go with a bottom diffusion system with the pump that Bill is going to recommend. Use 1/2" ID self sink airline, not 3/8". You only need one diffuser in the pond. You could go with a 1/4 hp pump and have more air than you need.

Run the numbers on what each pump would cost per month to run. 2 hp vs. 1/4 hp. Say running 30 days, 24/7.

Thanks guys, I'll get on this and report back....

Yes: water pump, not compressor. My contractor has recommended all along a setup w/ a waterfall, for functionality as well as aesthetic benefits.

The pond is ~12' at its deepest. KWH is ~$0.12. He'll have piping along the bottom leading up to a ledge where large carefully-selected slabs are being readied. He'll drill through the slabs to connect w/the piping. I trust my contractor, based on everything I've seen over the last few months.....from his expert work w/the excavator drilling through solid rock for weeks, then after he returned from a long layoff (due to a medical condition), he correctly determined the areas where the original company had done faulty work (incorrectly compacting the clay, issues with how the banks were created, the spillway, etc, etc.), and corrected everything; he does careful, thoughtful work, including expertly installing the 14,000 sq. ft. liner w/little help. So, I'm inclined to trust him. I was just hoping I might not have to spend that much for the pump....but in looking around online, I see that (so far) The Pond Guy's price on the pump doesn't seem out of line.

As long as the waterfalls water is with drawn from the bottom of the pond, a water pumping waterfall will be aesthetic and somewhat functional as oxygenation. Operated enough hours per day during water temperature stratification periods (55+F), then the pond can get an acceptable water column turnover per day. Numerous factors influence the functionality of the waterfalls oxygenation process. IMO there is no way a waterfall will be as efficient both as oxygenator and as economical as a bottom based aeration system. But who can put a price value on good aesthetics? Waterfall are for aesthetics.

Firstly I think your contractor is incorrectly estimating/calculating the water volume in your 1/4ac 12ft deep pond. If we had a square or rectangular box that was 1/4 ac (10,865sqft) and the box was 12 ft deep this = 130,380 cuft X 7.4gal/cuft = 964,812 gallons and close to the 972K gallons estimate of the contractor. Pond are not boxes nor cylinder shaped swimming pools. Ponds have sloped sides, not vertical sides as in a box.

Rounding numbers - IMO a 1/4ac 12ft deep pond with an average depth of 5.5ft will have around 10800sqft with around 439,000 gal . The 2 HP planned pump is rated at 11,000 GPH. This calculates that it will take the pump around 39 - 40 hrs to fully circulate the pond and to pump, lift, move 439,000g. Even an average pond depth of 6 ft gives 479,500 gallons. Ponds normally have shallow beach areas that further detracts from the box shape and if it had 4 very steep sloped banks of 3:1 slope. Every 3 ft out gets 1 ft more depth 9 ft out = 3 ft deep.



For future reference - My experience is a 1/4 HP rotary vane air compressor that is operating a 3 head 9" membrane disk diffuser can move and mix 439,000 gallons in 1.25 hours. However the sound and aesthetics are definitely not the same as a waterfalls. A 2 head disk diffuser on the same compressor will mix and circulate the 439,000 gallons in around 2 hours(1.9 hours). A one disk 9" membrane disk diffuser will mix and circulate 439,000 g in around 3 - 4 hours. Mixing the new 1/4ac clear water pond with a low biochemical oxygen demand once every day for 1.5 to 2 hours with a 2 or 3 head diffuser should keep the pond well destratisfied and oxygenated. You might want to consider a bottom based aeration system as a supplement to the waterfalls?.

Stoney Creek in Grant Michigan has both submerged and non-submerged pumps for waterfalls. They have one submerged pump for <$1,500.00 that pumps 17,500 gph. Stoney Creek Pumps

Sorry for the delay; lots to think about. My inclination is to go with the suggestion to "consider a bottom based aeration system as a supplement to the waterfall."

I LOVE the idea of the waterfall and believe it will be a wonderful addition. However, let me understand this: are you saying that the waterfall will take 39-40 hours to accomplish the same job that the compressor would in 1.5-2 hours?? If so, then I'd definitely plan to implement using both waterfall and compressor. Our waterfall will have on/off easily available, and contractor says I can use it when/as I wish. So my thinking is I can enjoy the waterfall mainly for aesthetic reasons, and use the compressor every day for a couple hours to ensure proper oxygenation/aeration. Am I thinking about this right?

The bottom based air compressor system will fully circulate the small pond in 2 hrs IF there are the correct number of diffusers operating with adequate air flow volume as noted in my above post. Fewer diffusers results in longer mixing times. Bottom based aeration is based on air flow volume and the number and placement of diffusers. Do it half-way and you get half- way results.

Yes.

Moving water with a pump is more efficient that compressing and pumping air.

However, there is a giant efficiency advantage when the air goes through the diffusers. The BUOYANCY of the tiny rising air bubbles lifts a huge column of water towards the surface - much greater than the water being moved directly by your waterfall pump.

My wife has already approved the exact same design as you have described above for our next pond. Aeration system to keep the fish happy, water feature that can easily be turned on and off to keep her happy!

Okay, so I'm convinced: we're definitely going with the waterfall + compressor setup.....the compressor w/diffuser for daily oxygenation/aeration function, and the waterfall for aesthetics.

I've started looking at compressors for prices/features. So far I've checked out Stoney Creek and Living Waters; there are definitely others out there. If any of you have specific recommendations/suggestions for the best place to buy the equipment, that would be great.

Here is a link to the Resource Guide. Those are the suppliers that help support Pond Boss.

Pond Boss - Resource Guide

I believe(?) some of the major manufacturers will then refer you to a local dealer after they help you size and design your system.

If everything is going to be shipped anyway, you might switch from your local dealer to some of the people you may know from the aeration threads that are also dealers.

[If those recommendations above are a little off base, I hope the people that buy more stuff for their ponds can correct my post!]