Composting bins can be made in all different shapes and sizes. This video does a review of 10 different composting bins and tumblers. They find that the bins reach the highest temperatures–about 140 to 160 degrees. The compost tumblers reach about 130 to 140 degrees. The hotter the better for making compost.
There are some drawbacks to the composting bins:
- It is much easier for animal visitors to get into the compost if you are using food scraps.
- In order for the composting to be quick you need to turn the pile.
- It is hard, physical labor to turn the pile.
- It is time-consuming to turn the pile.
They talk about air circulation which is a real plus for composting and some of the bins have a lot of holes for great air circulation. (Though these holes can be a problem if you have animal visitors because it is easy to get into the pile.) There was a complaint that the compost tumblers didn’t have so much air circulation because of a lack of air holes. I disagree because a lot of air circulation happens in the tumbling which is one thing that helps tumblers create compost faster.
Lastly they show a compost tumbler which didn’t have a proper mix of greens and browns. I was very interested in this because I did the same thing with my compost tumbler. See this post Greens and Browns in Composting. I quickly corrected the problem with the addition of browns or carbon to my compost. In my case I used peat moss. It was in the middle of the summer and I didn’t have shredded leaves around. This is indicative that composting with tumblers is not perfect and you can mis-manage them just like you can mis-manage any compost pile.
Here is the video of the review of compost bins ( http://youtu.be/-lCVcv04K5Y):