<a href=showthread.php?s=&postid=6934985#post6934985 target=_blank>Originally posted</a> by Rueg
You need to use it to kill the flatworms. It can be doesed in the main tank, but you need to run a ton of carbon to remove the toxins from the flatworm die off. Preferable the carbon should be run in a cannister filter to force the water through the carbon. I noticed when I used it that many of my bristle worms and other critters died. I believe it was from the massive flatworm die off rather then from the FWE itself.