Ideal for ponds, Pond Boss Pond Skins Pond Liner is reinforced with a sturdy, but lightweight mesh weave. It is easily manipulated and manageable in all temperatures. Its textured surface promotes beneficial bacteria growth making it safe for fish and plants. The liner is made of 14.5 mil PVC and is puncture and UV resistant. This quality liner is critical for the adequate development and dependability of a pond and its components.