How to: Do it Yourself Filters for Fish Ponds
- 1). Wash the crate thoroughly with a soapy solution to remove dust, chemical residue or contaminants. Set aside to dry.
- 2). Measure across the bottom of the crate from side to side. Cut a piece of aquarium filter matting the same size as your measurements. Fit the matting into the crate, pressing down on all edges to secure it. If the matting is too large, trim it down to fit so that it lies flat and doesn't buckle.
- 3). Measure each side of the milk crate from the surface of the inserted matting to the bottom of the upper crate lip. Cut the matting in as long of a piece as possible to fit around the sides. Cutting out each piece individually will work, but leaving the matting in one continuous piece eliminates trying to fit the corners together.Insert the matting into the crate, pressing it down to meet the bottom layer of matting. Trim the matting so that it does not extend beyond the bottom edge of the crate rim. This space is needed to ensure the top layer of matting will sit flush with the top edge of the crate.
- 4). Fill the bottom of the crate with a 2-inch layer of gravel or lava rocks. Place your pond pump on top of this layer.
- 5). Cut a hole in the side of the matting just large enough to allow the pump electrical cord to pass through. Feed the electrical cord through the hole. Cut another hole in the side of the matting if the intake tubing is located on the side of the pump. Push the tubing through the hole.
- 6). Fill the area around and on top of the filter with the mesh pot scrubbers. Pack them in firmly until they are level with the top edge of the matting sides.
- 7). Measure the top of the crate and cut the matting to size. Fit the matting into the top of the crate until it is flush with the top edge of the crate lip. Trim any excess if the surface is not laying flat. If your pump tubing is located on the top of the pump cut a hole in the top matting and feed it through. Connect your tubing to your water feature and plug the cord in. Submerge the filter into your pond and turn the pump on.
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