Big boulders are probably much more useful (aesthetics)out of the water or at waters edge than submerged below the surface. Boulders by themselves create very few places for small fish to hide; few nooks & crannies. Boulders under water also only provide a few places for ambush predators to hang out. All sizes of tree limbs are much more useful for fish habitat.


aka Pond Doctor & Dr. Perca Read Pond Boss Magazine -
America's Journal of Pond Management