Get a bag of all mix / complete mix, any kind of prefertilized soil and transplant that plant into it. Use at the very least a 1 galon (4 liters) pot, 2 or 3 gallons (7 to 11 liters) would be better. Also, as long as the ph is between 6.0 and 7.0 it is ok, you probably over flushed, leaching all nutrients from the soil in the cup. Another thing, get an EC/PPM meter, i will help when it's time to feed.
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