[rhythmicfire]

May be flatworms (plararia sp.?) Either way, I'd just take some airline tubing and vacuum out what I can before water changes. Be wary of just smashing them as such because I believe they release toxins into the water when they die. While one may not produce a whole lot of toxins, when you use a medication (which I don't recommend) that kills large numbers of them, the toxin concentrations go up. Maybe a sixline wrasse will help you out - not promised though.