So i bought purigen for my fluval c4 a couple months ago, but didn't use it yet because i still had some activated carbon bags left over for my fluval c4,so i wanted those to use those first so they i didn't buy them for nothing. So my question is will purigen lower my nitrates? I test my water parameters at least once a week sometimes more, and my water parameters are always ph:6.5, ammonia:0, nitrites:0,and nitrates:5. Im just worried that if i use purigen it will bring my nitrates down to 0 and my tank will have to cycle again. All comments will be appreciated, thanks.