If your bin is heating, you are doing something wrong. Your bin should not be heating up at all. If it is heating a little bit now, it could heat more and kill your worms.

If the bin is heating, you are probably over-feeding.

I don't know what to do about heating. I have had heating problems, but my bin is large enough to allow the worms to move away from the heat. I was able to just wait it out. Your bin is smaller.

If you can identify what is heating, you could try removing it from the bin. Or perhaps pull it up to the surface and push it over into one corner, so the worms can move away from it.

A soil based mixture does not work well for composting worms. (That is not causing heating, since minerals don't decompose and heat up.) You want to use less soil and more cardboard.

Old potatoes take a long time to break down, and they can stink if they are whole.

I found the source. it was green grass mixing with the card board. im working on my mixture i have a bunch of schreded office paper that is getting moist and then ill have more than 60/40 mix to paper to loose soil. the worms are doing well getting large #'s just a smaller looking worm. although i do a lot of fishing.

I should have figured that the grass was the problem, but you made it sound like you didn't have that much grass in the bin.

Grass should be dried or hot composted for at least two weeks before it is added to the bin.