consistently 0 nitrates?

[madagascariensis]

hmm, the tank is new, none of the rooted plants are growing yet, but I do have 2 and a half square feet of frogbit thriving at the surface of my tank...
hmmmmm...

[mizzoutank]

i still think you are moderately stocked, so the nitrates produced aren't that high.

and even though your plants aren't growing as you say, they are still acclimating and taking up those nutrients when available.

so that combo would easily balance out the 0 nitrate reading you see (if the test bottle is used correctly)

[Cliff]

I would say your nitrate level is likely between 1 and 4 ppm which your test kit will not pick up on.