Gravel or Rock in a Phoenix Pond

Over the years, Phoenix backyard ponds have been constructed with a variety of materials. Many are made out of concrete, while others use preformed plastic tubs or various types of flexible liner. One of the main reasons we advocate the use of gravel is that it plays a vital role by providing a natural habitat for beneficial microorganisms. It’s also a cost-effective way to cover the liner and enhance the ecosystem, making your Phoenix backyard pond a lot lower maintenance!

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The rocky bottom of a Phoenix backyard pond is alive and brimming with activity, covered in algae, microscopic invertebrates, and bacteria. This section of the pond is basically a compost pile. When organic debris falls to the pond’s bottom, it’s broken down by the benthic (bottom) inhabitants. These organic recyclers live off of uneaten fish food, decaying plant matter, and nitrogenous fish wastes. If this substrate wasn’t present, the pond would quickly die, effectively being suffocated by toxic fish waste and organic build-up. If you don’t have this substrate, draining & cleanings must be done often to eliminate that build-up.

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Fortunately, nature has given us a way to solve this problem with your Phoenix backyard pond. And it’s SO much easier to work with Mother Nature, than against her! Organisms have evolved to use practically every bit of available food. Fish, crustaceans, and aquatic insects will feed on these minute organisms, including bacteria and algae that live on the rocky pond floor.

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In addition, gravel lends structural stability to the Phoenix backyard pond. To achieve this, gravel is placed in between and behind the boulders. This eliminates spaces between them, which keeps them from shifting around, giving you a stable substrate. The gravel becomes a free-floating mortar, naturally locking the boulders into place. Again, Mother Nature does this as a matter of course in the naturally-occurring ponds and streams.

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When adding gravel to your Phoenix backyard pond and waterfall projects, be sure to vary the size of the gravel in order to provide a more natural appearance, as well as stability. You can have your gravel mixed at the stone yard, incorporating a blend of 3/8” to 3” gravel. The larger pieces give mass to the gravel bed, and act as a nice transition to the larger boulders. The smaller sizes provide lots of surface area, which is key for the pond’s biological activity.

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