I would guess that your current food intake just increased proportional to the number of calories you're using will be fine. The foods you're eating right now are very easy to find in SE Asia, and I think macro balance is fine (though I'm no scientist).
Regarding electrolytes, find a solution that works for you. It could be tablets. My personal preference would be to get a bag of rock salt and dip my eggs in it, as well as eating fresh fruit. You may also find that the salted peanuts there are very salty.