Ohhh... well above 60 ppm... I know it's sad... thankfully I gave away the poop-machine Molly and 3 Zebra danios. After they were gone, I used a API Master Test Kit to test the nitrates. (This all was BEFORE I did the massive water change) I could hardly believe that my fish could survive in that amount of nitrates in the tank! If you have an API kit, you know that the red color on the card is very bad. Well, that's where my water was. I was so alarmed, I did a 90-95% water change within the next 10 minutes! (Afterwards I was randomly researching Neon Tetras, and found that it was a miracle that they survived the water quality fluctuation) The next day I tested the water and the nitrates had thankfully dropped to adequate levels. thing is, my tap water nitrates are at 0-5 ppm, so I thought, "Why doesn't my fish tank water have such low nitrates? Can I do another water change to reduce it to very healthy levels? I need to ask an experienced fish keeper." So now here I am.