20% of the pond surface area is the figure that I like to see used when figuring out how much cover to put in a pond. Design it so that you have thick cover near bedding areas for small fish to hide in, more open cover in some other areas for the predators to ambush their prey from, and also have thicker cover in the deepest part of the pond.

Even if you don't have an aeration system in the pond and the deepest water is unavailable for the fish to use during the summer, they will need that deep water cover for winter.

That allows the smaller fish a place to hide during the winter, and concentrates the predatory fish around those areas, making it easier to catch fish during the winter months.

Without the deep cover, (or rather cover in all water depths) if the water drops, it's like the fish are living in a bathtub, and the forage base can be over eaten.

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3/4 to 1 1/4 ac pond LMB, SMB, PS, BG, RES, CC, YP, Bardello BG, (RBT & Blue Tilapia - seasonal).