Forum Moderators: rogerd
While your posting volume is low, if your software permits you can put new threads or even posts on "notify" so that you can see what's going on without having to log in as often. This will also show up a spam attack in its early stages.
If you are deeply involved in the topic of the forum, you may need more time to post yourself. You'll want to be sure members are getting replies, and you may want to craft some conversation starters, tutorials, etc.
The time you'll need is proportional to the posting volume and new member activity. A forum with no activity takes no time to manage, but is kind of boring. If your forum takes off, though, you won't be at that ten or twenty posts a day for very long!