Yes, you can do the one bin method. But be aware that the beetles will eat the eggs and the pupae. That's why most worm keepers keep their beetles separate.
Oatmeal works fine for beetles, and you can heat treat it the same as the bran. It scorches more easily so be careful to stir it a few times. You don't want to "brown" it, just heat it.
The oat meal and other heavier grains are a hard environment for the larvae (worms) to swim in, and they swim and crawl throughout, not just on top. The small fry, especially like to hang out below the surface, and are happier in wheat bran because it's the lightest medium.
The only problem with the two-bin method I described is that the frass may also sift down into the second bin along with the eggs. For that reason, most of us use oat meal for the beetles substrate. That way, only a small amount of frass filters down. Frass is waste, and if there's more frass than edible substrate, the worms may go into a kind of shock since they aren't getting enough to eat.
If you have beetles and larvae all together, and you go to scoop out some worms, you are going to get beetles, too. Many people are put off by the beetles because they will cling and crawl on you at the slightest touch. They have a habit of crawling where you don't notice them, and later reappear in the strangest places. People swear they don't fly, but I've had them get loose and learn to fly once they've adapted to freedom. I learned this one night when one flew into bed with me. I heard it buzz over and then felt it land on me. I was very surprised, when I turned on the light and saw what it was, that my one of my beetles had actually learned the art of flight.
Oatmeal works fine for beetles, and you can heat treat it the same as the bran. It scorches more easily so be careful to stir it a few times. You don't want to "brown" it, just heat it.
The oat meal and other heavier grains are a hard environment for the larvae (worms) to swim in, and they swim and crawl throughout, not just on top. The small fry, especially like to hang out below the surface, and are happier in wheat bran because it's the lightest medium.
The only problem with the two-bin method I described is that the frass may also sift down into the second bin along with the eggs. For that reason, most of us use oat meal for the beetles substrate. That way, only a small amount of frass filters down. Frass is waste, and if there's more frass than edible substrate, the worms may go into a kind of shock since they aren't getting enough to eat.
If you have beetles and larvae all together, and you go to scoop out some worms, you are going to get beetles, too. Many people are put off by the beetles because they will cling and crawl on you at the slightest touch. They have a habit of crawling where you don't notice them, and later reappear in the strangest places. People swear they don't fly, but I've had them get loose and learn to fly once they've adapted to freedom. I learned this one night when one flew into bed with me. I heard it buzz over and then felt it land on me. I was very surprised, when I turned on the light and saw what it was, that my one of my beetles had actually learned the art of flight.
Now since I only have 2 drawers what kind of difference should that make? I assume I should cut the bottom out of the top drawer and replace it with wire (will hardware clothe work or is that too big? or should I use like window screen?) So I put my original worms in the top drawer to let them grow and turn into beetles…then their eggs/teeny worms fall through to the bottom drawer and that is what I can start feeding to the chickens but I should also let them grow into pupa..so I was thinking maybe when i scoop some worms out I should just put some back into the top drawer and those will be allowed to become pupa and then beetles and reproduce etc.
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