There's a few aspects to your test results that are worth commenting on. The first is phosphate test results. Because of the chemistry involved, and the range we're looking for in reef tanks, the judge-by-eye wet chemistry phosphate tests are nearly useless. There's just very, very little color difference between zero (actually, below the kit's limit of detection) and the typical 50-100ppb phosphate that is advised for an SPS tank. This is primarily why the Hanna Checker phosphate assays are so dominant in the hobby. The chemistry is the same phospho-molybedenum blue color reaction, but the electronics in the checker itself are far better at discerning the color difference from this chemistry in the low range of phosphate concentrations than any hobbyist's eyes.
The second comment is about nitrate and the API nitrate test. I've not used the API in quite a few years, but if they've not changed it, properly executing this test is problematic for most reefers. Particularly the part about shaking one of the reagent bottles and the completed test sample thoroughly. For this reason, I'd recommend choosing another brand.
But the overall aspect of my comments isn't about the specific test kits chosen, it's about the importance of the specific results. For very experienced reefers growing "stick tanks" (i.e., acropora and other SPS), yes, keeping nitrates elevated above zero and phosphates in the 100ppb range does matter if the particular aquarist keeps the tank at a high pH and/or higher alkalinity range. Otherwise, the combination of high pH/alkalinity AND very low to undetectable nutrients may cause loss of SPS corals.
However, for beginners, especially those with brand new tanks that may contain "easier" stony corals, the nitrate and phosphate concentration in the tank water just isn't that critical, and it would be advisable for the budding aquarist to concentrate more on establishing the habits necessary to keep specific gravity, temperature, alkalinity and (to a lesser extent) calcium stable in the tank. That's particularly true if the aquarist doesn't yet have an ATO and/or 2-part dosing pumps.
