It's difficult to tell but on the face of it, it looks like a 0ppm result to me.
The API nitrate test is notorious for giving false zero results. The reagent is a powder which seems to easily precipitate out of the solution. If it is not properly dissolved, it won't change the colour of the liquid.
The instructions, IIRC, say that you have to shake the bottle for 30 seconds before adding the drops. Ignore that. Shake the bottle for at least a minute or two, give it a good bang on the table to dislodge any bits of powder that are stuck to the bottom of the bottle, and then shake it again some.
Try it again, and see what it comes up with then.