polyfilter

["paul" <paulalundberg at yahoo_com>]

Early last year Daphne wrote that she used a Polyfilter to test if she had
copper in your tank.  Reported that no copper was 'sorbed, but it removed
iron she didn't know she had.

Is the polyfilter suitable for planted tanks or does it work too efficiently
in 'sorbing Fe, K, NO3, etc. that are needed by plants.

I saw Polyfilters mentioned as a positive intervention on a freshwater
shrimp list today.

Any thoughts or experience?

Paul