sure, FYI- Mg and Ca get locked out of soil in ph 6.4 and under so def. raise up that ph to 6.8 or little higher first. I think your feeding for next time should be maybe 1x a week, and I would increase to that now. I would keep the ppms where they are. Just make sure you are using a bloom fert with little nitrogen and more potassium and phosphorous. does it have the N-P-K ration on your bottle?
She looks good, those spots would def. be from too low of ph but she looks quite well otherwise. You will not see improvement in those affected leaves but it should not spread to any other large fan leaves and do check constantly.