i guess i haven't been treating for it long enough (not hot enough) -- thanks everyone for the pointers...

I'm guessing that you're refering to the post with the vortex diatom filter? Yes, this filter will remove ANYTHING bigger than 1 micron from the water. I'm treating a tank now by raising the heat to 87-88 and running the diatom filter to remove anything that survives to enter the water.gil;717810; said:so what does this do exactly? filter out the parasites?