i have heard of that, what it does is create an area for anaerobic bacteria to grow, which convert nitrAtes to nitrogen gas... you need a sandbed of 3-6" of depth and some creatures to sift the sand (sand sifting stars, nassarius snails, etc)
i have a shallow (1") sandbed in my 24gallon NC and have kept 0 ppm nitrates for the last two months (tanks been set up for 3)
i have a shallow (1") sandbed in my 24gallon NC and have kept 0 ppm nitrates for the last two months (tanks been set up for 3)