Pond Boss Forums AERATION Systems questions Using waterfall for aeration

I'm in the planning stages of pond approx. 150' x 80' with avg. depth of 8'. One bank is about 8' higher than water level and I plan to build a water feature (water fall) for areation. What is the formula for water turnover (GPM)I need to achieve? I'm trying to size my waterfall pump to achieve the correct flow.
thanks

also can you provide guidance of what sites I need to study to help in creating the right design the "first" time.

I think a waterfall into a pond would be asthetically beautiful. Depending on how high the water has to be pumped will be one factor in determining how many GPH your pump will be. I'll let the experts chime in on how effective surface aeration is vs. diffusers on the bottom. I will say this, I'd hire a professional to build the water feature. Its a little more than placing some rocks on a slope and turning on the water. They aren't cheap, but my small waterfall turned out great. I'll look for a photo.

Ray, the last aeration system that I installed was designed by Sue Cruz at Vetrex and I believe she designed slightly more than 3 complete pond volume "turns" per day. (That's without looking at the specs).

Somewhere there is a formula that tells you "if a waterfall is "X" wide and you want the water to be "X" deep going over the waterfall you need "Y" gallons per minute.

If you sucked the water from the bottom of the pond, I think it might be better than sucking the water from the top of the water column.

I have a friend with a nice waterfall that is maybe 6 feet high with good water volume. I'll go by there today if he is home and take some pictures for posting.

thanks esshup,
I was looking for the suggested "turns" in order to maintain good O2. I can calculate the pond volume and the GPH from the waterfall pump but my unknow was the "turns". If that number is 3 per day, I'll back into the waterfall flow rate. I was expecting a much lower number but that was a SWAG.

I'm going to be building 2 ponds. 1 smaller approx. 100' x 80' with the waterfall as an entry water-feature. This is an existing spring fed stream with an existing concrete low water crossing danm. The 2nd pond will be about 1 1/2 acre and requires excavation and construction of an earthen damn.

Questions - How do I set up a project site on Pond Boss to document the project progress and issues (with pics and video) and secondly suggestions of forums/sites to research before getting started. Lots of questions about soil and sealing. I've researched quite a bit but there is sooo much consider in order to get it right the first time,

ray

Ray, go to building habitat sub forum and start a new thread for the build process. You can document it with pictures as it progresses like others have done there.

As for where to search, that's a crapshoot. I'd look into ornamental water features or pond waterfalls (google) for information on waterfalls and pumps. You are blending 2 different aspects into the pond, ornamental and functional. There's not a lot of info here on ornamental ponds, but that subject does come up once in a while.

Look into the pond construction sub forum here, and also look in the resources guide for a couple of books on building a pond. I have a few of the different pond books and I think they are a good addition to the home library.

Maybe call some of the vendors here that offer aeration systems and see if you can pick their brains on how many turns and how a waterfall vs. bottom diffusion aeration differs.

Also, I would call the PB office and see if they know of any pond builders in your area. Even if you have to pay a consulting fee for one of them to come out, it might save you $$ and headaches in the future.

This is my friends waterfall. He wasn't home or I would have had him stand in the picture as a reference for the height of the waterfall. I'm guessing it might be 7 feet to the top rock.

Nice waterfall, I especiall like the way the source of the water seems to be hidden in the pine trees. Looks very natural.
thanks

Thanks for the feedback. I did review the "resources" section and found a couple of companies. I sent a request to them so se'll see what kind of a response I get. I'll also call PB and get the name of some pond contractors in Central Texas.

Typically 2-5 turns per day are recomended, however, for what you are doing I would not be concerned so much with how many times you are turning the water. There are so many other variables to consider when constructing a waterfall for function as well as aesthetics. When applying the principles to achieve your desired results typically you will exceed the recommended tpd. As you can see from the photo above there is not enough aeration going on there to be adequate for the size of feature your are looking at building. I always tell my customers to go with the biggest pump they can afford. Not only the purchase price but also the monthly expense for operation. Design your system so you draw water from the bottom 1/3 of the column but not on the bottom and have your pump on the opposite side of the feature as your waterfall to keep the water circulated. Also when designing your waterfall keep aeration in mind. Instead of spreading the falls out like the above photo use narrow streams that run quickly over rocks churning the water and increasing the d.o. have several of these streams running into your bow and entering the bow at different locations but not directly over the pump. Then as part of the waterfall have a rock extending out at a high point and let the water fall from it 6 feet onto boulders at the bottom. Using this combination will optimize the d.o. from the waterfall. Keep in mind running water errodes so use a liner for your streams and your falls. Also get creative and use longer runs in your streams but keep them fast and churning.

Thanks for the design insight. They all make a lot of sense. Once I get the project underway I'll post some pic's.
regards

Some other things to consider. Check the power consumption of the pump you want to use. You might end up spending a pretty good chunk of change to run a large waterfall pump 24/7. Air pumps typically will aerate water for cheaper than water pumps. On the waterfall pump i would recommend pulling water from the other side of the pond from the water fall or a deep point on the pond to help insure proper mixing of the newly aerated water as it comes off the waterfall. You can also put a T in the suction line to draw from 2 or more points if you feel it's necessary. The easiest way to build a waterfall is probably to set a pond liner under it and stack the rocks on that to help insure minimal leakage. To avoid problems with your pump make sure you plumbing
Lines are properly sized, but as a general rule of thumb, bigger is better, especially on the suction side. Often times undersized or long suction runs will cause the pump to cabotage which makes them noisy and drastically shortens their working lifespan. Correctly sized or slightly oversized plumbing will contribute to you pump moving the maximum amount of water for the amount of energy used, by reducing the dynamic head pressure. Plumbing that is drastically oversized will can also reduce the efficiency of the system because the static head pressure is increased enough that it offsets the reduction in dynamic head. Also if you can try to use "sweep" 90s instead of the typical hard 90s of you can as this helps to allow water to flow more efficiently.