Aeration is the biggest key to a healthy pond and fish and the first tool to invest in, it is an investment similar to building the pond, but now we want to keep the pond alive, even reverse the aging process. When an aeration system is properly calculated and designed for your pond we are able to turn over the entire volume of water once a day which will supply the pond’s oxygen demand. Here’s what happens when the pond is aerated properly with a bottom diffused aeration system. Take for example a one acre pond 12’ deep in the center and the bottom floor is shaped like a bowl.
Sitting at the shoreline is a ¼ hp rocking piston air compressor, from the compressor the air travel down weighted rubber tubing to the bottom diffuser. Once the air reaches the diffuser it emits tiny air bubbles. (These are rubber membrane diffusers, not stones) These tiny air bubbles race to the surface of the pond, as the race to the surface they are each pushing, pulling and en-training water along with them.
After these bubbles reach the surface of the pond they simply pop and the water carried with them creates a “boil” of water, so to speak. This boil is all the water these tiny bubbles have pushed up. In addition to moving water they also push out the toxic gasses from the bottom of the pond which contains carbon dioxide, hydrogen sulfide and ammonia. The result of these tiny bubbles racing up from 12’ deep water is approx 3800 gallon per minute of water movement, with a ¼ horse rocking piston compressor. The continued movement de-stratifies the water tension allowing oxygen to be absorbed and pushes water out to the shoreline, essentially stacking the pond with oxygen.
With the pond now having the oxygen demand met a few new actions can take place. Fish can now use the entire depth of the pond, essentially making more room for more fish and the pond more inhabitable from top to bottom. With oxygen, good bacteria known as aerobic bacteria can thrive at the bottom of the pond, their job is to consume muck and debris built up each year making the pond shallower and over time would fill in the pond.
Beneficial bacteria’s will now be able to reach the depths of the pond due to the oxygen at the bottom. These are aerobic bacteria’s and thrive in oxygen rich water to consume nutrients left from decaying weeds, leaves, fish waste and everything else that falls into the pond. When the pond does not have adequate aeration those toxic gasses build up and could very well end up with a fish kill.
Don’t get me wrong there are bacteria in the pond but these live without oxygen and produce these foul smells. They also work on the decaying process but are so slow at it they can’t keep up and the pond eventually fills in with muck.
The second effective tool is adding beneficial bacteria’s to the pond. Usually along the shore line and let the diffuser pull in the aerobic bacteria to the bottom to working on the muck. Along the shoreline is generally the worse area for muck since this is the warmest spot of the pond, weeds and algae grow mostly in the shallows and depending on wind direction floating debris ends up along the shoreline.
Don’t worry I know it sounds strange to add bacteria but these are the good guys and yes there could be bad bacteria in your pond from too many geese around, livestock pasture or the septic tank and leech bed are nearby. In the event of fecal coli the aeration system will help to precipitate these toxic bacteria’s.
The specialized bacteria treatments we use are a formulation which contains multiple Pseudomonas cultures, as well as Bacillus cultures. It also contains beneficial enzymes and a growth nutrient to help break down the debris and be consumed reducing the sludge and muck build up plus suspended organics. You’ll see different products for water clarity and sludge and muck reduction, both products have the same make up but the major difference is the sludge and muck product has more of a concentration of bacteria for the bottom muck while the Pond Clarifier for water clarity is reverse in its bacteria make up.
Treatments or the dosage rate of these bacteria products are every two weeks, sine the bacteria do multiply and move around in the pond they also start to die off after a couple weeks.
This is the simple two step method we’ve used for years and have had no problems with algae, like we once had. Back then the pond was almost as green as the grass and raking algae out almost every day. But once we go the correct aeration system sized for the pond it’s no more rakes and the only green is the landscape around the pond. So I’m not caught in a lie we also use pond dye to give the pond an amazing color.
One last note on aeration bacteria treatment and dye is they are not harmful to the environment, wildlife and domestic animals. We’ve been using these products for up to four years now and our dogs drink from the ponds. As do the deer, geese, ducks, turkey and all forms of natural habitat in and around the pond with no ill effects.
In depth details about Pond Aeration can be found in Darrell's book, Pond Aeration 101, different types, how the work and the pond life cycle.
Aeration systems should be designed and calculated for each individual pond to assure proper water movement and that the oxygen demand will be met for that particular pond. Click to see more information on Proper Aeration.