https://steemit.com/colorchallenge/@kalemandra/new-colorchallenge-for-all-steemians
Here is the original #colorchallenge post. I use this one for one post a day and then usually do a second the depends on what pictures I have.
https://steemit.com/photocircle/@photocircle/photocircle-project-update-new-tags-for-top-10-daily-contest
These are good tags also