When you drive by some great looking large ponds, and particularly those on golf courses or commercial properties, it’s not unusual to see the beautiful spray of water from a floating fountain cascading through the air. There’s no question pond fountains are popular and provide a great display.
Contrast this to the more covert pond aerator that sends air to the bottom of the pond. In man cases the most you’ll see is some ripples and light bubbling at the surface of the water. They seem so subtle in there work, most people won’t even notice that they’re there.
The question often comes up wondering which one of these systems is best. To appropriately answer this question, it’s best to compare to the two and also discuss the types of ponds that they work best in. There’s no question that each system is unique and different, and depending on the circumstances, one is really better than the other in our opinion.
Pond Fountains And Surface Bubblers
A pond fountain, as the name implies, creates a fountain of water from a surface based system that draws water up through it and propels it upward and into the air. There is usually some type of doughnut shaped float that keeps the whole assembly suspended and the motor as well as the intake pipe will lie below the surface.
Fountains can vary a lot in terms of their power and with various fittings or nozzles the spray pattern can be adjust to suit many tastes. One might even see lights attached to the system.
Many people prefer fountains because they do provide a very attractive and appealing aspect to a pond. The sound of the droplets of water landing back in the pond can be relaxing and the spray patterns today are varied and attractive.
Another, less attractive, but very functional device that you might see floating around is some type of pond bubbler or surface based aerator. The purpose of these is not geared towards aesthetics but more for functionality. They move a lot of water and provide an increased degree of circulation of the water.
Both of these systems create enough agitation at the surface to help with the oxygen exchange that all ponds benefit from.
Aeration systems are simple in design and function. They use a land-based compressor or pump that’s connected to an airline. This airline runs from the pump to a diffuser that sits at the bottom of the pond. The diffuser may come in several configurations but all of them use very fine holes that are punched in a rubber membrane and air is driven out through these holes and into the water.
A very fine array of bubbles are released in a column that shoots up to the surface of the pond and this causes a bit of agitation there that, much like the fountain, will help the water grab oxygen from the air above. In a sense the surface of a pond is like a plain or barrier. As this barrier get’s disrupted, either by a mechanical action or even waves on the surface, more oxygen can be pulled in from the air above.
An aerator also creates a bit of a rotational circulation of water which goes up to the surface, along the surface horizontally, and then back down and across the bottom of the pond.
Aeration kits can be adapted to fit most any size of pond and larger compressors and multiple diffusers are common in very large ponds that are over an acre in size.
The Pond Counts Too
Which brings us to the question of what ponds will benefit from either of these systems. In truth, any pond will benefit from some increase of circulation and surface agitation however there are two primary aspects of a pond that will determine what will work best on it’s behalf.
Depth is probably the number one determining factor in which system will work the best. If a fountain is your kit of choice, a shallow pond will actually benefit more from these. Because they are at the surface and draw water from a few feet down, most of the circulation and all of the aeration occurs at and near the surface itself. If the pond is much over six to eight feet deep, one can still find low oxygen levels in deeper ponds.
There are shallow aeration systems that are designed to work in depths of six feet or less but for the most part, both of these designs are about equal in how they handle shallow waters.
As depth increases to anything over 8 to 10 feet aeration kits become more and more attractive to helping with the over all health and well-being of the pond. While it’s true they don’t help much with the look of a pond like a fountain would, they can actually keep them cleaner and healthier because they assist in increasing dissolved oxygen in deep areas of a small lake. It’s these spots where oxygen is inherently low and if it is, aerobic bacteria, which helps to clean up organic elements in the pond will be hindered quite a bit.
So, in a round about way, submerged aeration can actually help to keep problems like algae blooms in check which in turn greatly improves the appearance of the pond itself.
It’s also quite possible to use both systems together if the need should call for it. Normally you would see this in a very deep and large body of water that can benefit greatly from aeration and where the owner may still want the look of a fountain at the surface. The two systems integrate just fine with one another.
Fountains And Aerators Compared
As we wrap up this discussion on fountains and aerators let’s look at how they stand up against one another in comparisons.
First of all, when it comes to costs, in most cases a comparable aeration kit for a particular pond size will be less expensive than a fountain. This isn’t always the case but usually you’ll find a difference of several hundred dollars if not more.
Fountains are more prone to plugging up since they pull water into them from down below. If there is a lot of plant growth or debris in the water, this can get pulled into the intake and the fountain output will be affected. We’ve even found masses of tadpoles in one unit when they hatched out one summer.
Aerators on the other hand use a land based pump to push air into the water so they tend to be more trouble free. Diffuser heads can get covered with muck if they aren’t run for a time but usually since air is being pushed out of them, they stay clean throughout the season.
Operational costs may vary a good bit as well but many fountains use larger pumps than an aerator kit would and this can lead to a bit more cost to run them. For very large bodies of water it’s very likely that your aeration system will need to use multiple diffusers. These should be spread out evenly through the pond area. A good rule of thumb might be about one diffuser per surface acre of water, however if a pond is shallow, it takes more diffusers to cover the same area. Greater depth is a benefit to getting more out of a diffuser package.
Installation for both systems is relatively straightforward and simple so they are similar in that regard.
In summary, our suggestion is to consider a fountain, surface aerator, or a shallow aeration kit, if you have a pond that’s less than 8 feet in depth. If your pond is deeper than this it might be a good idea to shift your research to a traditional aerator kit that will provide more benefits in deep water. In making these considerations, you’l be getting the most out of your investment and improving the chances of getting great results in your pond.