I figured that much.  I was nervous that it was possible to leave it in too long so I took it out within 10 minutes.    My goal was to get rid of all the crud off the rocks so I can cycle them in my tank.
It's way too cold out now to be screwing around with water outside.
Best thing to do now?  Cure it in a container in the basement?
I guess other people can learn from this 
