Wall Lake residents have been busy all weekend cleaning up their docks. Last week's wet weather created low oxygen levels, killing thousands of fish in the lake. "It's the cycle of life unfortunately.  And sometimes, it's not pretty," Wall Lake resident Kristi Golden said. Golden has lived on Wall Lake for 14 years, and while she understands the power of nature, she didn't think it was this strong.  "You'll get maybe a handful of them, but nothing where you're seeing hundreds of floating little white bellies and hundreds on the rocks," Golden said.  "It's really something." Golden and her family have been clearing the fish off their dock since Friday, and the problem's so bad that South Dakota Game, Fish & Parks has set up dump sites both at the lake and at the Sioux Falls Regional Landfill.