[AFJuvat]

Problem: After changing the water on my 300 gallon saltwater tank, I had a sudden spike in the amount of nitrite (NO2) in my tank; it was 0ppm and jumped to 0.5ppm.

After confirming that there was not a problem with my tank or equipment, I tested my tap water and found that the nitrite levels in the water straight out of the tap was about 0.75ppm and the nitrate (NO3) levels were 5 - 10 ppm

Nitrite is toxic to fish, and I am to understand that it isn't exactly great for humans either. Does anyone happen to know what the acceptable level of nitrite is for drinking water?

Thanks