Ah ha! You did not mention this, just the fish food though to only have 5ppm of nitrates from 4ppm of ammonia is questionable. Is this after doing a big water change or before?
JLK - i misspoke. I did the 24 hour test, ended with zero ammonnia and nitrites, and plenty of nitrates. At which point, I did a significant water change (90%) and tested the water again ended with 5ppm nitrates...at which point I added my baby black moor.