My experience has been such that my planted tanks were always infested with BGA off and on. I would constanly be adding erithromycin to kill it and it would stay away for about a month. Test readings showed slight traces of PO4 and no traces of any nitrogen source. I was informed by a fellow hobbiest to increase the KNO3 and this should be a better long term solution in balancing out the bio-available phosphate. So to test this method, I put 1/2 tsp KNO3 in the water of my paludarium. This tank is a half full 20gallon long which has a carpet of riccia growing on the rocks near the water fall that was completely coated in BGA (wet but emersed) and under water as well. The very next day there was no visual sightings of BGA anywhere, although the smell was still there. One day later the smell was gone as well and there was no water changes at all involved in or around this treatment. Since then I have not had the pleasure of fighting this smelly, slimy, photsynthetic bacteria. Of course this is my own experience and yours may be different. Steve ------------------ To unsubscribe from this list, please send mail to majordomo@thekrib.com with "Unsubscribe aga-member" in the body of the message. Archives of this list can be found at http://lists.thekrib.com/aga-member/