Foam is a common problem in many water features. Excess protein in the water leads to bubbles being formed by splashing water. EasyPro defoamer is a silicone based product that prevents foam bubbles from forming.
Safe with all types of fish and plants. Foam is not only unsightly but also increases the oxygen demand on the pond.
If your pond's surface is frozen over, Do Not break the ice, doing so could harm your fish. Instead, use warm water to melt a hole in the ice or use a pond Deicers to keep a hole open.