Episodes of tachycardia on a few occasions out of the blue. started eating more potassium and within weeks the episodes stopped. connection?

Yes: Electrolyte abnormalities can generate ectopic beats or trigger tachycardia. Potassium and magnesium depletion can result in tachycardia by their effect on resting membrane and the possibility of triggered arrhythmias. This can occur in situations of excessive diuresis or volume depletion.

Likely: Hypokalemia (low potassium) is associated with tachycardia. There are also other causes of tachycardia. A cardiologist can help you, especially if your symptoms return.