Using Cacti to monitor availability

[YodaVonBeck]

I have been experiencing some internet connection drops and wanted to monitor this using a spare RPi I have.
So I just did the installation and set up a few devices like the Google DNS, my router and other stuff - just to learn.

However, it seems the ping check is only every 5min and I would like to be able to check something every 10 seconds.
I found this old discussion: viewtopic.php?t=56897 but I am a little uncertain if the current version of Cacti would be good. Tried to change the default to 30 sec, but it does not seem to capture it, when I look at the graphs....

How would you suggest I do this?

Thanks!