The document presents research on using anammox bacteria to remove nitrogen from dairy wastewater in constructed wetlands. The objectives were to enrich anammox bacteria in phase I and seed wetland systems in phase II. Two filter systems with different media sizes were built and showed no significant difference in total nitrogen removal. Ammonia and nitrite decreased while nitrate accumulated over time, indicating partial nitrification and anammox activity. More data is needed to better understand the nitrogen removal processes.