I think you are referring to Mallory run, the out flow of Edinboro lake. Conneaut creek is in Albion.
I have always heard its a grey area below the kids area its the area right at the outflow of the lake. Adults fish all up and down that section. So where the kids area ends and open fishing for anyone on private land (with permission) I cant say.
I know people get trout there, they are stocked, so they are there. It is a small creek and I am sure since these fish were just put there, they would be scattered with the major concentration at the outflow where the kids fish.