Confused by my Drop Checker readings

[cfrank]

I'm a little confused by my drop checker readings at the moment. I woke up this morning to find it quite yellow-green. It is the sera brand tester. The confusing part is I have no source of CO2 within the tank to speak of at the moment. Yesterday it was dark green before I put any plants in, and I only put in 7 small-medium sized plants. I'm presuming that their little bit of respiration over the night caused it to change to yellow-green. My CO2 system arrives later today, and I have yet to add fish to the aquarium. The water level is down about an inch from the top so that my HOB creates a fair amount of disturbance. pH has been reading 7.2-7.3 by my test kit, while kH has been kinda low, ranging down to 2 drops after a water change and up to 4 drops after it has been in there a while. Ammonia is being eaten up like it's going out of style, but both my nitrites and nitrates are sky high (both dark red on my sera test kit), even after a 40% PWC yesterday.

Thoughts?

 

[Brian_Nano12g]

A couple of things come to mind... first off, are you using tank water or a 4dkh reference solution in the drop checker? Secondly, as for the reagent (Bromthymol blue), which are you using (i.e. comes with the kit, API pH test, eBay a la China, etc)? I'm unfamiliar with a sera brand DC.