Thanks guys! I ended up starting with hp to spot treat the worst area(s). I had to throw out the Java Fern (it was rotting, smelly, and covered with quite a bit of cyanobacteria on the roots/rhizome). It wasn't in good shape to begin with. In regards to the Erythromycin, do you guys recommend a particular product? I'm sure I will just end up buying this to resolve the problem for good.