Where to trap leeches in the brainerd lakes area

Hi my name is Brayden and im 14 I really want to trap leeches for fun this spring. I live near pequot lakes and and tried last year using beef liver to chicken guts (like 30 ponds) using coffee cans, burlap and pie pans. but could not find any ponds with ribbon leeches. My little brother is helping me as well and I don’t wanna let him down this spring again Any help would be appreciated. thankyou in advance