Potassium Iodide in Flexicolor - Which part?

Hi,

I've been mixing up my own flexicolor starter since I couldnt get any, what I've settled for a recipe on works pretty well for me (except recently I've had weird density problems which I think is from contaminated developer at this point, just a fresh batch up)

I was wondering if anyone knew which part the Potassium Iodide content comes from?

It's not the starter is it? I haven't accounted for KI in the starter.