I've tryout many things. But what I've found was that since I found using cold water with tiny amount of PF I won't try anything different. For Me I will not develop a rl unless I have PF handy. Where I am @ we have very soft wtr so it works as the direction indicate. other places with different qualities of water it doesn't work the way they claim it should. So experimentation is a solution, it just takes a while.