Sounds like we've all got similar problems guys... I've got a bad case of valonia going now too and find the best thing to do is manually remove it with a piece of rigid tubing snugged up to some vinyl tubing and siphon it out.
The rigid tubing will pry it up off of the rock or whatever else and then it just gets siphoned out. I'm sure I'm not the only one to try this, right?
I'll take a pic of my weapons of choice and attach it to give you guys a good idea if you haven't already tried it!~
Nope Dave, thats what I have been doing.