Been battling valonia now for a few months.  Have 20gal so fish who eat valonia are no go.  Have dropped in 4 emerald crabs.  They've been in there for weeks now and barely touch the stuff.  Been doing manual removal.  Very difficult as I have to remove each rock, remove valonia, and sanitize area where valonia removed.  I'm VERY hesitant to remove bottom rocks as I have two anemenies and a sea cucumber suspected or known to be attached to or under the rocks.  Basically I'm at a point where I have to remove the bottom rocks to clean them.  Is this just a terrible idea?  Will emeralds become more interested in the valonia if I'm more patient?  I'm also worried this level of disturbance, essentially removal of all rocks in tank, will have a negative impact on the other inhabitants.  Any advice or ideas on this issue is greatly appreciated!