Maybe nasty worms don't dig phosphate? Got ready to do a water change tonight and came upon this creepy scene: Got at least a dozen 10"+ This one lost about 6" trying to fight extradition and that's at least 10" left over. I did steal the pump and heater over the last 24 hours to make a new batch of water, so I'm going to try that again in a few days and see if letting the temp drop for a day or so flushes any more out.