The still, calm pond outside of the Markee Pioneer Student Center is not so quiet four feet below the surface.

More than nine koi fish endure the winter months in the pond—thanks to a water heater and an aerator.

The water heater floats at the top of the water, and the aerator sits at the bottom, shooting air through the water.  The aerator supplies the water with oxygen and helps prevent the water from becoming stagnate.

Seasonal upkeep

The koi are self-sufficient and will feed off of algae and plants in the water, according to Steve Cullen, a groundskeeper who maintains the pond.

The groundscrew just needs to keeps the water clean and prevent it from freezing.  Before winter, they clear out any leaves or waste and remove the waterfall pump for storage.

“We then leave the aerator on and put in the water heater,” Cullen said.  “If the pond freezes over, then the oxygen level will deplete and the fish will die.”

When spring time comes, Cullen and his co-workers will remove the fish with a net, put them in a tank and drain the pond for cleaning.

Coy koi

“The fish usually stay at the the bottom of the pond,”  Cullen said.  “I’m sure some people have koi at their home ponds who are more friendly because they get to spend more time with them.  We don’t have time to play with them and treat them like pets.”

Koi fish are a type of carp who have naturally-curious personalities.  Some koi—if familiar and comfortable enough—can be hand fed.

The pond was created 12 years ago and is surrounded by rocks and vegetation.  During the warmer months, the University of Wisconsin-Platteville groundscrew will turn on a waterfall for added apeal.

“I think a lot of people enjoy it,”  Cullen said.  “Before, all that was there was a patch of grass, and I don’t know how excited people get about grass.”

The groundscrew will find an occasional straggler when cleaning the pond.

“Originally we bought 9 koi fish, but it seems there are a lot more,” Cullen said.  “We aren’t sure if they are reproducing or if some people are putting more (koi fish) in.  We have found goldfish, catfish and bass in the pond before.”