Pond Boss Forums AERATION Systems questions Water circulation and movement

I'm a fairly new pond owner, and this is my first post. Here are the pond specifics:
Built 2 years ago this month.
Retention pond, about .22 Ac (150' from levee to opposite end, about 75' front to back). Deep end roughly 11 ft, shallow end avg. 3-4 feet (when full) Run off comes from...a large hill on the back which is a cattle pasture(lightly grazed), large hill on the front which is my yard, and also a hill on the narrow end that has a home on top, about 200 feet away. Both end's completely covered in trees, and the fence row on the back side has some pretty big trees along it.
Waited one year to try and let water settle, clay bottom, so it was 'very red' for a long time. Still have somewhat of a problem with it, but definately improved.
In Sept 06 we put in, 200 CC, 100 redear, 100 HBG, and 3 'cups?' fathead minnows.
In March 07 we put in a 9" diffuser with a piston compressor (runs 24/7). Salesman said plenty big for my pond, I think 1/3 HP maybe 1/2, can't remember.
This year we have started having 'nutrient' problems, scum on the top, bubbles, duckweed went crazy! The duckweed rope skimmer from one of the Pond Boss members saved the day! After we skimmed twice in 7 days, we put in 6 oz of Sonar. Since we haven't gotten any measurable rain in the South for 30 days, I'm hoping it has killed the DW seedbed!
Now - for my confusion....
Because the pond is a rectangle, and the diffuser is on the far (deep) end, we do not have any water movement on the opposite end. Basically, my pond is like water half way up in a glass, very little wind can get across the top because of the hills and the trees. We are looking to add a 'top' water aerator in order to mix it up some. I think the diffuser is doing well as far as oxygen, but I do worry about the opposite side. We have caught a few of the CC (and released) they look healthy! Some are now 12" or so, and are healthy eaters! Extension agent should be coming when he has some free time, but would love to know what you all think. I've only made it this far, because of all the info we've gleaned from PondBoss.com! THANK YOU! THANK YOU! Absolutely love my pond, so any/all advice is appreciated!

Welcome, TPG.

Maybe the compressor is big enough to handle output to a second, shallow end diffuser. If you can post the make, model number, etc. off of it, someone who knows beans wrt aeration can probably advise.

TPG,

If it is a 1/3 hp you should have no problem adding a second diffuser. Depending on the CFM requirement of the 9" you have alredy installed, a 1/3 hp piston compresso should produce 4.4 cfm at 30 psi. if it is a Thomas Wobl compressor.

The 9" you already have most likely uses only a maximum of 1 cfm so you have extra cfm to use for a second diffuser.

By the way welcome.

This is all the info on the motor:
Thomas
A Gardner Denver Product
Model #689CE44 C
3.6 A
115 V 60Hz
Motor #608593C
I would love to post a couple of photos of the pond. Not a computer person tho. Can some one give me the "Idiot's Guide" to posting photos.

See the Archive thread on posting photos.

Pond Girl,

That compressor produces enough to add a second single 9" diffuser.

Cary is correct on adding a second disc.That pump produces 2 cfm open flow and 1.8 cfm @ 10 psi, I would be VERY concerned with your stocking rate as it is heavy for your situation, I think with your low water lack of wind etc that you may be headed for the same situation as Donnie Castle(please read that thread on dead fish)The duckweed that were removing some nutrients from the water column are now available to spawn other algae types also.Keep on eye on the CC for piping or gasping on the surface and have a plan ready to go that is beyond just adding a second diffuser, Your demand for oxygen may be fast catching up to your supply, good luck and thanks for posting.

Ted,are you sugesting that duckweed COULD be a good thing or did I misinterpet your reply.Ill try to give you a call if I get the chance .Wanted to talk to you about my diffusers also.

Ted - Donnie Castle's story sounds MUCH like me. Now I'm scared to death! about 12 days ago we put in 48 packets of "Nutri Defense" from Airmax Ecosystems. 3-4 days later the scum was back on the pond. But-a couple of days later it looked better than it had in a long time. Tonight, fish are still eating well, do not see any sign of gulping air. I'm wondering if I should go out in the morning to see if they are.
Just saw a horizontal aeration system from 'letsrodeo' and have asked him for instructions on setting up something similar, unless you can make suggestions on that. Can you give me some emergency instructions that I can start on tomorrow. Temperature today was 103 and saying 101 tomorrow. The past two weeks have been similar! 10-12 degrees cooler forcast for next week (hoping).
One more thing - can you please tell me the # of fish we should have based on our size?
Trying to post some photos from photobucket. In the boonies were I am, I'm practically on dialup, so hopefully later.
Donnie if your 'listening' I feel for you, and am shaking in my boots!

OK - here we go:
This is a picture on March 23, you can see the lay of the land and the placement of my diffuser
http://s238.photobucket.com/albums/ff266/auntpammy/?action=view¤t=IMG_0219.jpg
This is when we knew we had a problem, a couple of weeks after this we were covered with DW
http://s238.photobucket.com/albums/ff266/auntpammy/?action=view¤t=IMG_0491.jpg
This is a few days ago, we are assuming the green streaks are algae?
http://s238.photobucket.com/albums/ff266/auntpammy/?action=view¤t=IMG_0878.jpg

TPG, are you still feeding pellets? If I were you I would stop or at least significantly reduce the quantity.

I don't know much about maintaining fish in ponds but I've had my share of aquariums. I also worked in the local pet store when I was young and the owner was an ichthyologist. He always stressed to people that the primary reason for bad water quality was overfeeding. He said that with aquarium fish you could stop feeding and the fish wouldn't starve for quite a long time. In a pond I think it's accepted that you don't NEED to feed at all, and I'm sure that I wouldn't be if I was in your shoes.

Please don't act on my advise without hearing from someone with more practical knowledge though.

Good luck and welcome to the forum.

Pond Girl, here is my take on your CC stocking in your size pond.I would stock up to 100 (per acre) with other fish in a non feeding situation,unless you plan on harvesting on a regular basis then perhaps 200 per acre, feeding in small ponds as GW eludes to can cause problems from both digested and undigested nutrients.A small pond is a lot easier to manage without supplemental feeding, (feed a few for fun is not as much of a problem.) Stock 1500 per acre in ponds over an acre with a supplemental feeding program in a CC only pond and up to 7000 per acre for the experts doing it commercially.The later two programs would be harvested on a regular basis with DO monitoring equipment.My comment on duckweed was to get one thinking about altering a natural condition, Not a problem taking DW out but those nutrients will be there for something else to take avantage of, perhaps something not as invasive as DW.All water bodies have the POTENTIAL to pull more DO than a system can supply thus one could say that any aeration system has the "potential" to be undersized. In the situation of Donnie Castle any system in my opinion would of been undersized for as Cary put it "The Potential"as when a bloom starts to go south it happens faster than aeration can supply DO.A backup plan is fine but I would consider pulling some CC out when it is feasible (fish fry)Your water looks turbid and that normally does not lead to planktonic algae, that many CC may keep things stirred up but that also lowers DO levels, its all about balance and I dont want to see your situation get out of balance.We have had 5 situations of fish kills in ponds under 1 acre in the last 2 weeks and two of them had Kasco surface aerators which do a fine job, In all situations the fish stocking was heavy and created a demand that outweighed the supply,then you start over.

Thanks for your ideas. We have cut back on feeding and my husband has hooked up the boat motor for some extra agitation. Caught one CC yesterday that was about 2 lbs. Looked healthy. I think we are going to have all the nieces/nephews, aunts/uncles over for a big fish catching event and have a family fish fry. Try to lower the population to less than 100. Then do the same in the spring, maybe get it down to 50.
The pond is for fun, future grandchildren, etc.
So we got to be able to feed them!
What would you consider the 'best' aeration 'system'. Both a bottom diffuser and a top water circulator?

Im not sure there is a "best" aeration system, that is a very good question.If you have both a bottom diffused and a surface aerator you have more bases covered. A ponds need for oxygen (BOD)can change quickly, You can get more accomplished with a bottom diffused system if a pond does not create a sudden overwhelming demand for DO.Bottom diffusion will lift a lot more water than other systems but at the same time warm the entire water column (not good for cold water types)great if you are trying to decompose bottom organics.Bottom diffusion will do a better job at eliminating the daily highs and lows or DO swings.My experience tells me that once a pond starts to crash even kicking in a surface splasher usually does not help (but cant hurt)I think if a pond needed both systems (other than the splasher for backup) that the demand should be lowered instead of trying to increase the DO supply.About 70% saturation in warm water is about the best you should plan on with any system at sea level and at 86F that would be 5.25 ppm and less as your elevation increases (4.9 ppm DO @ 2000ft)I think you are doing the right thing by lowering your demand before nature does it.PS Do add that second disc soon.

One more thing - the diffuser that we have is air stones(4) instead of a disc. I have seen a disc that is to be used as a replacement for the air stones assembly, and says that it does a better job. We were thinking of getting the disc and swapping it out with the air stones (deep end)and then moving the air stone assembly up around 5 foot depth. My husband is even thinking about getting 3 or 4 discs and a larger compressor.
Would that be a smart move?

If you are running a 4 stone setup like the Sweetwater ALA4GL then your pump is maxed out, (1.5 - 2.4 cfm needed) even the smaller 4 stone ALP4 needs 1.2 - 1.5 cfm,if your not sure which stone you have the AES webpage is http://www.aquaticeco.com. You may have a different setup all together.Depending on the disc your looking at it might not be any different than your stones.It could even be worse. If a disc or any diffuser does not have independent test results published that state lifting capacity at varied cfm's at varied depths it is probably just a water water diffuser, nothing wrong with those in a waste water situation but can come up short in a pond and lake setting.Also look to find a waranty of at least 5 years and you start to thin the crowd real fast. We are in the process of adding a page to our site that will help you compare diffusers and how they perform in real world situations. I find most of them do well in the lab (bath tub) testing but often do differently when several months or years of everyday pond/lake use.Results on Ecologix,ATI,MixAir FlexAir,Sweetwater,Vertex,PermaCap,EDI etc etc,will be posted this fall to help one compare and make informed choices. Another short coming is the idea of a diffuser that self cleans,many diffusers are touted as "self cleaning" ALL diffusers need to be cleaned, the fashion in which you do this is what varies. Continue to do your research as you have found a great forum to get answers and direction.Not sure if this helps answer "What would be a smart move"

Ted,

You nailed the cleaning issue on the head. We have found our customers misunderstood the self-cleaning and I can see why. We are pushing the fact that calcium deposits are cleaned off the diffuser membrane by the expanding and contracting of the EPDM rubber.

But as with any diffuser, the organics will build up and a simple sweep of the hand over the diffuser membrane cleans it off.

We have looked into all kinds of methods of eleminating this problem from bottom boat paints, acrylic paints, electrolisis and even a biocide (not labeled by the EPA for aquatic use) that took care of that idea, and have not found a way to prvent orgainic build up.