elemental potassium Vs overdose

[Clever Mouse]

Hi, I've been supplementing potassium gluconate in powder form, at a couple teaspoons/day to help with dieting (low potassium intake), and proper electrolyte balancing. I think potassium becomes toxic at higher intakes, like 16+ grams or so. Would that dosage be from *elemental* potassium (540mg from a teaspoon)? Or the actual weight of the powder (potassium bound to gluconate?) (3448mg from a teaspoon).
Thanks!