I've seen that a lot too but unless there is some dangerous element elevated I ignore it. Not sure why it says that sometimes even when everything is in the green. I've so far only followed the water change advice to remove Tin and it was 100% gone after only 2 15% water changes vs. the 6 recommended. I wouldn't blindly follow the Triton advice without thought.LOL every time I send in a sample Triton tells me to do water changes! If it isn't corroding equipment it's some sort of contamination from food, dosing, or RODI water. I believe this last contamination was coming from NO3 dosing (contamination was Fe and Pb). I figured something was up because the NaNO3 solution I mixed had a slight grey precipitate. New NO3 solution from Loudwolf brand 99.6% pure NaNO3 mixed clean. Best defense is weekly water changes.
From the United States my ICP came back in seven days but still waiting on N-DOC .