So I did a 30% water change today with gravel vacuuming. Added my normal dose of Prime & Flourish (this is new the past 2-3 weeks). Tonight my fish were all at the surface, even my albino BNP had come out from his log & was hanging out closer to the surface, snails, everyone. Added an extra dose of Prime just because. Re-tested the water tonight: ammonia = 0, nitrite = 1.0! Last night: ammonia = 0, nitrite = 0, nitrates = 10-20 Tap water Tonight: ammonia = 0, nitrite = 0 (shocking, since last tap water test on 3/15 my tap ammonia = 4!, nitrites have always been 0) Where did this nitrite spike come from? Getting ready to do a 50% water change on the tank, since my source water seems to have 0 nitrites. @CindiL?, @jdhef?, @TexasDomer? anyone have an idea what is up?