Yes you can, I do.

When you put the hydroton at the botton of your pots, it makes the roots work harder since the first thing they want to do is find the bottom, so by adding some resistance, allows other roots to start making their run for the bottom and overall makes the plant stronger.

I don't use it for drainage, since my soil drains well. So, unless you're using "dirt" no worries. :thumbsup:

gl