Compost tumbler check, anyone?

Hi all, new to composting and to compost tumblers.

The mix in the picture is a few scoops of soil plus a good portion of torn up cardboard and paper, and an increasing amount of vegetable scraps. I was putting in my coffee grounds until the other day when I was warned off from doing so.

Since a couple of days ago I've been wetting it down with maybe a liter of water per go.

And we don't forget to turn it after adding more stuff!

The ratio of brown to green is probably about 2:1. It smells, not bad, but like Something Is Happening.  And it's a little bit hot, not steaming though.

I'm concerned that the cardboard strips aren't breaking down. I tore most of them width-wise so that they're not as thick as regular packing box cardboard.

Thoughts / suggestions welcome.

Hey Amy,

My thoughts only.  I would continue to fill (yes to coffee grounds and filters) and turn your tumbler until you get it 1/2 to 2/3rds full.  
Then wet it well, stop adding to it and turn it every few days until you get compost that is finished to your liking.

Hopefully, you have another spot to put your composting materials while you are waiting on your tumbler contents to finish.

Then empty the tumbler and start fresh or add your pile to the tumbler and repeat.

Good luck,
Keith

Hello.
My tumbler is small, so it does just cold compost I can't say how hot it is (not much), but the cardboards are breaking down well. What I do now is to soak the cardboard before introducing it in the tumbler, so it gets humidity right. In addition, I don't need to add water in a while, since the cardboards come saturated. If it takes too much for you, probably it is not wet enough.