Glad your plants started growing for ya. I bought some grow stones a while back,
I had huge pH swings with them, I found places online that said that you should rinse them, then soak them for 24-48hr, rinse again and the pH should stabilize. I don't have water at home yet...... So I couldn't do it very well. I never got the pH to stabilize. They now sit in the corner not being used. Someday I will soak them and try again.....