So this just occurred to me when I had a friend ask me how my aquarium is so clear and free of algae, and I thought I'd share it. I've been using high lighting in my planted tank for almost two months now, and just recently started using CO2 a little over a week ago, and have never had an issue other than when I first set the tank up. I think the secret might just be the purigen I am using in my HOB filters? The tank has been setup for about two years now, and during the first 6 months I did have issues with nitrate and algae, and ever since I started using the Purigen, I've never had an issue with excessive nitrates and/or algae. Anyone else have any similar experiences with this product?