To calculate the pond liner length, measure the maximum length of the pond, add the maximum pond depth twice and then add a minimum of 2 feet for overlay.

Keep in mind that it always better to have excess pond liner rather than be a few inches too short. Also, the two feet of of overlay will provide only one foot per side, so extra liner will make installation much easier.

Do I need pond liner underlay?
While pond liners can be installed without underlay, we recommend that pond underlayment be used under every pond liner. The pond underlay makes the pond liner more puncture resistant and will protect the pond liner from rock and sharp roots in the subsurface.

Is EPDM available in colors other than black?
No, and it is our experience that black is the optimal color for pond liners for water features. Lighter colored pond liners soon become unsightly because they showcase any dirt, debris or algae growth that is typical in water features.

Can two pieces of EPDM pond liner be spliced together?
Yes, it is a rather simple process using EPDM primer and EPDM tape. In-depth instructions can be found in the reference section.

What is EPDM?
EPDM is Ethylene Propylene Diene Monomer, a synthetic rubber material that is very flexible, puncture resistant and has unsurpassed UV stability even when left exposed to direct sunlight for decades. EPDM is also very easy to seam together and patch. Firestone PondGard 45 mil EPDM pond liners have a twenty year warranty and are without question the best pond lining material on the market today.

What is Flexible PVC?
Flexible PVC is made by taking PVC resin and adding plasticizers to make the material flexible. Normal PVC liners, such as shower pan liners found in home improvement stores, contain trace amounts of arsenic and other toxins that are lethal to pond fish even in minute amounts. However, those toxins are removed in the manufacturing of Fish Grade PVC. Fish Grade PVC generally does not have the UV resistance of other pond liner materials and should not be left exposed to direct sunlight above the water surface.

What is Polyethylene?
Polyethylene is a plastic material. Plasticizers are added to polyethylene resin to produce polyethylene pond liners. This material has very good UV resistance, but is rather stiff when compared to EPDM. So we don't recommend its use in decorative features that contain plant shelves and other irregular features found in most garden ponds. Polyethylene can be a good choice in larger ponds where appearance isn't critical. Because it is less expensive, lighter, and can be shipped as one piece so field seaming will not be necessary.

Should I put gravel on my pond liner?
Whether or not to add rock or stone to your pond is simply a matter of taste. Ponds with rock often look more natural but well designed ponds with bare pond liners can be easier to clean and maintain. If you do decide to place stone in your pond, use rounded cobblestone and use care when placing large stones.

Will roofing EPDM harm my fish?
Roofing EPDM may contain fungicides, fire retardants and other toxins that may harm or kill your fish. You cannot remove these contaminates by washing the liner, the toxins are embedded in the material and will continually leech out into the pond for years. We strongly recommend using a fish safe EPDM life Firestone PondGard in your pond.