The huge six-lane slide at Belle Isle re-opened briefly on Friday only to be closed again.
Kenyatta Mcadney said the fun turned to fear for his kids as speed became an issue.
"What I noticed was the impact they were hitting the ground with coming off the hills," he said.
The video shows a few wild rides on the slide as kids can be seen launching across the ride.
"I was going down way faster than I thought I was. Gravity hurts," Mcadney's child Keymarr said.
Michigan's department of natural resources, which runs the slide, closed the ride to re-touch the wax on the slide to control the speed.
"Hopefully after our small adjustment we will be back up and running and the slide will be slower for more enjoyment," read a statement.
Mcadney said he also gave up tickets he paid for just out of concern.
"If they would have kept riding on that slide, somebody would have got hurt," Mcadney said.
As of Friday. it is unclear when the slide will reopen to the public.