First I have to agree with rfeiller, as I've observed the same. Can I prove it scientifically? No but I've observed in my own tanks that fish are healthier in general when water is changed often enough to keep nitrates below 40 ppm. Isn't the object to mimic a natural ecosystem as closly as possible? Elevated levels of nitrates in nature reak all kinds of havoc on the ecosystem, so why wouldn't we strive to keep them lower in our systems?Originally Posted by urbanfarmer
Alright just for you some actual science.
http://ehp.niehs.nih.gov/realfiles/m...8056/8056.html