I have been running 0/0/0 for a month with no deviation. After two weeks of dosing a half dose (half of recommended dose for 20g tank) of Seachem Flourish Comprehensive, Nitrates have jumped to 5ppm and stayed there a week (ammonia and nitrites are still 0/0). Nothing else in my tank setup has changed other than adding the Flourish, though I didn't think it had much nitrogen in it. Is it responsible? And is 5ppm an okay level to run with? (I have a moderately planted tank).