how to not plot a built-in indicator

Using iATR in your EA will only refer to the indicator, it will not put the indicator on your chart.

but it does put it there (in a different window of course)

EA's have no hands, no mouse, they can NOT put any indicator on your chart. You (or your default/tester template) put it there.

You might be right about the indicators presence on the chart having something to do with a template. However, the templates don't have hands either and I am unable to reach into the screen to fix it. Never mind, I'll just figure it out myself.

Open a clean chart with no indicators attached

Attach your EA

Does the ATR suddenly appear on the chart?

If so, show the EA's code and somebody will tell you why.

Just to be clear, are you talking about using the EA on a live chart or are you talking about using the Strategy Tester?

I did manage to figure out the problem on my own. It only happens in the Strategy Tester and that makes sense. Thanks for responding without smart aleck comments.

Just include

HideTestIndicators(true);

 in you init.

Excellent. Thank you for a direct, precise and correct answer. My hat off to you and GumRai for offering real help.