just wondering i did a test on my tropical tank today and it read 20 ppm. is this high? i thought it should be at 0 ppm. how do i lower this if that is the case. can this cause the water to be slightly cloudy?
cane76 is correct. Unlike ammonia and nitrite which shold always be 0, nitrate will always be present in your tank unless it is heavily planted. It is the end result of the nitrogen cycle. Ammonia is converted to nitrite which is converted to nitrate. Nitrate is then removed when you do your weekly water changes. As long as it is under 80 ppm it's ok. Unless you have big waste producers it won't ever get that high between water changes.