Pond Boss Forums AERATION Systems questions Aerate for BOTH cold and warmer water fish?

Hey folks. Thanks again for such thorough responses. Thanks also for the greetings to the forum. I've been a reader for about a year but just recently subscribed to Pond Boss Mag and this terrific forum. A special thank-you to all the hard work done not only by the participating members but especially to the thankless work done by the moderators. Tough job for even tougher pay, lol!

To "Beastman", who asks if the photo of my ponds shown is actually 1.4 acres: My contractors charged me for 1.3 acres of dirt movement, the liner company charged me for 1.5 acres of pond-liner coming in at 12,800 pounds and my pond maintenance company - Aqau-Dock charge me for 1.4 acres of the new pond of management so is it 1.4 acres? I can't really say for sure, but as a photographer I can make the illusion of a look of a 3 or 1/2 acre pond depending on which lens I chose and angle of camera at the moment of the snap. This particular pic is a porch view with an iPhone FWIW. With it being a "C-shaped" pond I'm sure someone can figure it out, just not me. They tell me 8.5 million gallons of aqua hanging out down there. Those dozers dug and pushed for a month.

As for Mr. Cody's veritable response I'll cut and paste with my comments interspersed in caps for ease of which is he and which is me "speaking/writing".

"Welcome dhadam- I foresee potential problems with your situation and plan. ME TOO. The thermal tolerance of your fishery spans the full thermal range of common pond fishes. Not an easy fishery combination to manage successfully even in northern ponds. Trout are cold water adapted, WE, SMB, YP are cool water fishes, and RES, CC, sunfish and FHM are considered warm water species. Trout and the redears are the two outlying thermal species at opposite ends of the common sport-fish thermal spectrum. THE RESF WERE PUT IN THERE TO CLEAN UP THE SNAILS FROM THE WATER SOURCE TO FILL THE POND BESIDE THE ROCKY RIVER. I CAN'T SAY WHERE IT CAME FROM, JUST THAT IT PROBABLY WASN'T THE RAIN. ;-) HOPEFULLY THE 5 MOS THEY HAD BEFORE COLD WAS ENOUGH TO MITIGATE SNAIL PARASITIC INFUSION.

As you mix cold water in an ice covered pond you will lower the water temperature from the normal 39F. Usually regardless of diffuser depth. As winter aeration progresses the water continues to progressively cool below 39F, as this happens the warm water species will become more and more thermally stressed. When the water temperature drops below 39, I predict you will first see significant deaths of the redears. As aeration continues water circulation quickly involves more of the bottom water. As the water temperature drops from 38F toward 32F more thermal stress will occur primarily in the warm water species, then the cool water species, and then finally the trout. The thermal stress may not kill, but it will weaken surviving fish depending on species, water temperature, duration of the low temperatures, and water quality. MY RESEARCH INDICATED THAT @ 16'+ THE WATER SHOULD HOVER @ 62F. TRUE OF FICTION? ALSO, WITH THIS SIZE OF WATER WITH THESE THERMODYNAMICS (IF 62F IS TRUE) WILL IT BE OVERCOME BY OUTSIDE TEMPS EVENTUALLY? HOW DOES ONE MEASURE TEMPS AT SUCH DEPTHS? SOME SORT OF DEEP PROBE?

The thermal mixing characteristics of ice covered ponds during harsh extended winters have not been well studied and the effects are not well documented despite what has been posted on this Forum. Cold water mixing behavior is not the same as warm water mixing & circulation mainly because the density and properties of water change as temperature increases or decreases. This dramatically affects how water mixes during warm and cold periods. My experiences show the differences are dramatic. HOW SO? Most of the available winter mixing informational statements on this forum are just ideas and theories not proven facts. I have only collected limited unpublished data about winter aeration of ice covered ponds. More needs to be done for this topic. HOW CAN I HELP BRING DATA TO THE TABLE?

In my experienced opinion of aeration and water mixing patterns during ice cover in ponds, the currents and mixing regime is dependent on size of pond, pond depths, volume of air used, number and pore size of diffusers, location of diffusers, depth of diffusers, operation schedule, and sunlight penetration through ice and amount of the open water area. I think all these numerous variables affect the thermal mixing pattern from the diffusers.

Since your pond is new (1-5 yrs), with adequate depths of average 16ft in your case, I don’t think aeration will be necessary during winter unless deep snow completely covers the pond for greater than 10 to 16 weeks. At that point or prior to it, removing 15% to 25% of the snow cover should allow adequate photosynthesis to generate enough DO for all fish survival without aeration. In new ponds with little biochemical oxygen demand (BOD), and a significant percentage of deep water, adequate DO at the start of winter will last until the spring thaw. Whenever sunlight penetrates ice cover, photosynthesis from phytoplankton under ice can quickly oxygenate the underlying water in a matter of several to 12 hours. Most ice that develops beneath the uppermost top ice is glass clear. This allows sunlight to penetrate thick ice when snow is absent. A frozen slush layer depending on its thickness reduces the amount of light penetration. IF ONE HAS ALL AERATION EQUIP IN PLACE WOULD IT BE ADVISABLE TO SIMPLY HIT THE COVERED ICE WITH AIR ON A PERIODIC BASIS, SAY 30 MIN/DAY OR JUST GO PUSH SOME SNOW?

At the worst case the trout may die in winter when DO drops below 4ppm while all other species survive, but dead trout are doubtful to occur in a new deep pond such as yours. Your trout are more likely to die in mid-summer compared to winter. If the trout die in winter of 2017-2018 then try aeration winter of 2018-19. A low number of RB trout in a mixed fishery are relatively inexpensive to replace. IMO your main management at this point should focus on not having too high of a total fish biomass and this will result is less winter stress of the pond’s fishery and healthier fish going into spring. INITIAL STOCKING WAS WITH ALL JUVENILES (EXC.#150 1-YR RBT) AND #75 .75 TO 1LB HBG. 50WE, 12SMB, 300BG, 150RSF, 150YP, 7000 FHM, 60# NCF.

I would not be concerned with feeding the trout during ice cover because the pond has natural invertebrates and you stocked supplemental minnows, thus the trout can find enough to eat to maintain body weight. IMO I would use this first winter period as un-aerated and to create an informational baseline to learn about the winter characteristics of this new pond. SINCE I STARTED AND STILL AM AERATING SHOW I CUT IT OFF "COLD TURKEY" OR TAPER IT OFF THIS TIME OF YEAR? Next year you may want to experiment with aeration to begin comparing new data with baseline information from the 2017-18 winter. Fertile new ponds relatively quickly in a few years develop increased BOD requirements and this has a significant impact on the winter DO patterns of a pond. YES, SOME LEAVES ALLOWED IN, ALL HABITAT IS PLASTIC-WARE, I.E., HONEY-HOLE PRODUCTS. SO LITTLE DECOMP HAPPENING."

Thanks to all, especially to Mr. Bill.

Mr. Don