Here is the situation. Power is located about 500 feet from a small pond. I would like to put the pump near the power. Can I run hose or pvc the distance to the pond? If so, what is the max distance? Pond is under 1/4 acre.

Thanks

Texas715,

Your timing couldn't be better....just spent the day runing an airline from my large pond to the 1/4 acre TGG pond, a distance of about 400 feet. The large pond is also another 400 feet from the compressor.

It is absolutely no problem to push the air those distances....a far better option than running electricity.

I just hook up the middle buster on the tractor and dig the trench and lay the pipe. Takes very little time and effort.

I prefer to use pvc pipe at least 3/4 inch. Today I was using 1 inch for this additional line. I like pvc because of its durability over the plastic pipe...I can run over it on my equipment without problems. Also, the cheap plastic stuff isn't often pressure tested before shipping and you can have leaks.

How far can you push air? I've heard of guys pushing it 2000 to 3000 feet without any problems. Maybe one of the Vertex pros will chime in on this....by the way I recommend their diffusers and compressors also, really excellent.

If any questions I haven't answered, please ask. Thanks.

Hi Texas715 -
Meadowlark couldn't have said it better!

ML, Sue and others,

This question is tangent to the original post so I apologize but I'm curious to know if anyone maps out or marks the location of underground aeration lines for future reference/landwoners.

Currently, I have one aeration line running off the corner of my outbuilding to my BG pond. This line is only 10' long so its path is simple to see. I plan to run an aeration line to my other pond and thought about burying a piece of metal wire alongside the tubing for future reference. The metal wire would be something that could be picked up with a metal detector.

Russ,

Sounds like a good idea. In my case, it's easy to see the location because I mounded up a little over the pipe.

FWIW they use fairly small (14-16 gauge) copper wire buried with gas lines for detection purposes - I don't know if it works better than other wire or is just economical, but it must be sufficient.

Russ,

I just installed one mile of underground tubing in a golf course in Asheville. Same problem, no power at site but we could feed up to 5 AirPods off this one mile line.

The Golf Super wanted a way of tracking the line for future turf improvements and we added a 14 gauge copper wire as Theo said above to be able to detect the location. Using a simple metal detector, it worked great.

Maybe we should add this option to our product line? HMM?

ML to the rescue again. I thought for once that I would be ahead of you. Just a note that mound that you have over the pipe will more than likely not be noticeable after a couple of years.

You haven't seen my mounds, Texas715...

Here's a link to a good table that shows the pressure loss in a length of schedule 40 pipe. Since irrigation pipe is smooth plastic on the inside this chart should be good for that too. An example is that for a 3/4 inch pipe if you push 5 cfm through it you will lose 5 inches of H2O pressure. Multiply inches of water by 0.036 to get PSI. So in this case you lose 5 x 0.036 = 0.18 psi per 100 feet of pipe. So if you pumped this air 500 feet you would lose about 1 psi. So you have to add 1 psi to the pressure that your pump will be running at in order to get the CFM you want. This is in addition to the pressure caused by the depth of your aerator which is about 1/2 psi per foot then you need to add the back pressure of your aerator. So if you want to get 5 cfm out of an aerator that is 10 feet down you have to find a pump that will pump 5 cfm at 5 + 1 psi = 6 psi plus back pressure for your aerator. With this same example if you would use 1/2 inch pipe your pump would have to be capable of 5 cfm at 8.5 psi plus aerator back pressure. Bottom line is the pump needs to overcome the loss in the pipe plus the depth of the water plus the back pressure of whatever aerator you use. It would not be unereasonable to find that to pump air 500 feet a 1 inch pipe may let you get by with 1/4 to 1/3 hp pump while a 1/2 inch pipe may require a 1/3 to 1/2 hp pump. Moral of the story is even though you are only pumping air don't skimp on pipe size.

http://www.aquaticeco.com/index.cfm/fuseaction/popup.techTalkDetail/ttid/2

ML, it's good to hear that your TGG pond is so close to an existing air compressor. I assumed it was very remote. So you dont need the solar aeration system at all then, right?

BM,

The TGG pond is close to the airline that runs to the big pond(400 feet)....not the compressor. When Mike ran the numbers and determined that my existing system could support another diffuser and that another airline of about 400 feet was all I needed, then it became obvious that was the best solution for me in my situation. I just dug up the existing line at the closest point of approach and added a "T" and off we went to the TGG pond.

I'm still looking for a solar solution for additional yet to be built ponds which will be 1/2 mile from electricity...so prototype your system and let us know how it goes. Thanks.

You got me curious, ML - did you put in valve(s) for balancing the air flow to the two different ponds? If so, where at - the ponds or the "T"?

Yes, a valve for each diffuser and located at the edge of where the airline goes into the pond. After adding the third diffuser, I definitely had to balance to the air flow. The TGG pond is shallow, had a 1 inch line and the other two diffusers were in deep water with 3/4 inch lines feeding them. When I first turned on the air to the TGG pond it was like a fountain. Throttled it way back to less than 1/4 open on the valve and it still creates a commotion.

It's best to install the valve at the pond's edge so you can adjust it while looking at it. Ohterwise you will be getting your exersise running back from the compressor to see the pond and back to the compressor again.

Cary,

It gets even harder when two ponds are considered running off the same air compressor and spaced out where you can't see the diffusers in both ponds at the same time. ....yes I did several walks back and forth trying to get the airflow "right" in all three diffusers....just went by the looks of the air column generated. Maybe there is a better way?

Happy TGG and HSB, and that's a good thing. I have been wondering when is the best time to aerate in hot weather if there is not much vegetation or algae to cause 02 decline at night. I want to keep surface temps down, but seems that evaporation is greater if aerator runs during hot afternoons. Now I am running air from 3 to 6 PM, and midnight til 6 AM. Any thoughts?

I also run my air only at night here in Ohio. I run from 8:00pm to 8:00 am. It works out very well and also saves my pump from the heat of the day. I think it gets a little wormer in Texas?

Meadowlark, to adjust the flow to each diffuser, we use a thermal temp. gun. Grainger carries one for about $100. By adjusting the flow so each valve is around 5 deg. of the other valves, the flow is pretty even then. The only other option is to place a cfm flow meter on each valve, but at $50-$100 each, it is too expensive.

Bugermeister, the only true way to tell if you are reaping the full potential of your system is to test with an O2 probe. Seeing what is happening at the surface is like a poloroid snap shop or a doctor saying you look okay without doing a blood test.

If you must run your system in intervals, the times you are running it are the best. Keep in mind, most compressors are designed to run continously and not on and off. It takes a lot for the compressor to push that air down initially and if there is no way to stop the water from entering the air line, it must push that out too through the diffuser.

The compressor is like a plane taking off. It is full throttle until it reaches altitude, but then it backs off for the remainder of the flight.

Okay, enough analogies.

Cary,

Thank you for the post. I've been out-of-pocket all day and haven't had a chance to respond.

Do you think the "gun" is worth the money, i.e achieve better results than just the eyeball method? Is it something we average pond guys should have?

My situation is a single compressor providing air to two diffusers in one pond and one diffuser in another pond.

Thanks for your expert opinion.

Meadowlark,

I have this time been out in the field. Just returned...sorry for the delay.

No, no need to spend your money on that toy. Too many other toys out there that can be used more for the adverage pond guy and they can get pretty close to equalizing the boils simply by eye.

ML, just saw this post. I like the challenge of figuring out an easier way. I think that a very close adjustment of more than one air line from a single pump ought to be possible if you install one pressure gauge that measures pump output pressure and one pressure gauge in each of the other individual lines. It's not as simple as just dividing the pressure because flow rate is proportional to pressure squared if I remember my fluid mechanics. I'm going to take a look at the math behind this and see if I can devise a way. I have the same problem and it would help if there was a simple cheap way to do this. I have one pressure gauge at the pump already and adding one for each line would not cost much. Would avoid more expensive temperature or flow meters. I'll let you know if I come up with something.

bz,

I'll be interested in what you come up with....my configuration is the same as you described, i.e one pressure gauge at the pump only. The diffussers are at different depths, also.

In dealing with compressible gas, the mass flow rate varies directly with pressure....but I haven't looked at those equations in years and I think my doctor told me I couldn't do that anymore.

http://exploration.grc.nasa.gov/education/rocket/mflchk.html

ML, I here you on the equations. I'm getting some help from a buddy of mine who is better at setting up and solving mutliple equations than I am. He's got some equations for me to look at but since there is the possibility of varying line sizes, varying distances, different diffusers, and different depths it looks like it will involve calibrating the system by checking the back pressure in each line by running all the air through the line and comparing that pressure against the published flow rate of your pump at that pressure. So you'll need your pump performance chart and will have to take several pressure readings prior to getting this done. In the end the equations will give you the pressure setting for each line that will result in equally split flow rate. If this turns out easy it may be a good alternative to expensive equipment. I'll be trying out on my pond as soon as I pick up two more gauges.

Meadowlark, are you talking about a 3 point hitch middle buster that looks kinda like a plow? How deep will it plow and how big of tractor to you use to do this?
This may have solved a problem for me. My pond is about 650 feet from the last out building that I have that has power to it, only 115 vac 14 guage wire on a 20 amp breaker that isnt a single use application, but back to the middle buster!
You used the pvc pipe that is in 10' or 20' sections?


Does the plow make a clean enough ditch to just lay it in and then cover it up?

Does anyone use the black poly that is in 100 foot rolls? I believe it may be cheaper not sure though....Man I love this forum although I havent had much sleep this weekend due to all the reading

Oh my bad I just realized I replied in the middle of the post I didnt read on to the 2nd page so sorry

Trialsguy,

Yes, I use a middle buster off the three point hitch. I use it on a MF 55 hp, but certainly a smaller tractor could do the same thing only maybe a bit slower. It will cut you a clean trench 4 to 6 inches deep, if make at least three or four passes. Then just lay in the pvc...yes I prefer the 20 foot sections, less joints to make and cause problems. The hard part is covering up the pipe...it is somewhat time consuming.

Yes, the poly pipe is cheaper, but far less durable and I've been told it is subject to pin hole leaks from the factory.

I see you are from Oak Grove, Mo....grew up around Fair Grove and have several relatives in Ash Grove...lots of Groves in the Show Me State.