How long do you wait until you change out the oats to new oats? I have had mine in there for about a month and I just recently have seen some beatles in there. Do you change out the oats every month???
I use powdered gutload and change it when it starts to look more like mealworm poop than like gutload. WIth unpowdered oats, I guess they can stay in there (as long as they don't get moldy) until they're eaten up. Once the beetles start laying eggs, if you change the oats you'll be throwing out eggs and tiny mealworms as well.