I have found a way to recycle the tobacco that is still moist in the bottom of a funnel or vortex bowl after a session.
Wait for the tobacco to cool down, remove the dry hard stuff on top.
Roll up the moist tobacco in a ball and put it on the end of a stick.
Next time you have a campfire roast the shisha tobacco and inhale the aroma.
I call it Shisha-ka-bob!