It’s a fact that every single pond will benefit from increased aeration and oxygenation. Some ponds, however, have certain characteristics that can limit just how useful aeration can be, and the major consideration is the depth of the pond.
Simply put, the general rule of thumb is the deeper the better.
Depths of 10 feet or greater allow for greater coverage in a pond. What I mean by this is a single diffuser (or the part of the system that sits at the bottom of the pond and releases the air bubbles) can effectively treat up to about one acre of surface area if you have 10 to 12 feet of depth or more.
Conversely if the pond is more shallow than this, you would need multiple diffusers to treat the same surface area. Ultimately any aeration is probably better than none at all, but the goal is to increase or stabilize dissolved oxygen levels at 5 mg/L or greater. (Here’s a simple DO test kit if you’re wondering just where your pond stands). This DO level will ensure that fish are protected from oxygen deprivation, particularly in very hot and still days during the summer.
Over the years, I’ve always considered surface fountains to be somewhat helpful in shallow ponds. They don’t help as much in deeper water because they only affect the upper few feet of a pond, but again, they were usually better than no aeration at all.
Now we’re seeing a growing number of shallow pond aeration systems that are specifically designed for ponds of 8 feet or less and they are somewhat unique in their setup. If you have a shallower pond of around a 1/4 acre or more be sure to watch the video below to learn more about improving the conditions in your pond.