Hi guys. I bought the plant 2 months ago, and place it indoor at the southern window . Singapore weather on day around 33 °C or aka 91 F . In order not to overwater it , i water only when the soil is dry . I water moderately so is impossible for water to drain out from the holes.. maybe 3 seconds from a watering pot . I check with my finger and soil is moist from as deep as i can feel with my fingers. Before watering i will always insert my whole middle finger daily to check the sole moist before watering, will only water will the soil is dry.

Last week the weather was getting hot my plant start to lose leaves at alarming rate, maybe 5 per day on the ground .. and the leaves turning pale green and curled up. the pale green leaves are fragile that when i touched it, it will break and fall..I increase my watering slightly and add in oraganic fertilzer, but is not getting better: leaves fall off same rate and leaves start to curl up .

I not sure whether if is iron or magnesium deficiency , or lack of nutrients, underwatering or overwatering~, help!