Over the course of several weeks, I have noticed more and more tiny semi-translucent limpets covering all surfaces in my 20-gallon blackwater tank. This tank houses only neon tetras. These little mollusks continue to multiply very rapidly! The limpets do not seem to be causing any problems but they are absolutely unsightly. So far the only thing I have done is to use the rough part of a mag float to crush all of the ones on the glass but those on everything else and in the substrate still persist so by the next day dozens are back on the glass. How can I get rid of these annoying inverts?!?