Hi jeffteo,
Yea I just put it in yesterday night. Water cleared up significantly, previously I was having unexplained cloudy water.
Here are a couple of references:
http://www.seachem.com/support/forum...ead.php?t=2510
http://www.barrreport.com/showthread...n-Planted-Tank
Basically purigen supposedly doesn't remove nitrates which was an important factor for me (I'm dosing KNO3). Main aim was to polish the water up.
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