it will take much much longer than 5 months to get 10" IMO.
from what ive seen in the dovii i have grown, males grow very fast, females on the other hand do not. i had a costa rican dovii in my 600g for over a year, growth was almost non existant (maybe 1 or 2", it was about 9" when i sold it). i expericed similar non-growth with a nic dovii female i replaced my otehr female with. my tnak was getting a 50% water change a week, and all the otehr fish were growing very quickly.
maybe with excessive feeding, and tons of water changes the growth you will experience will be faster, i wouldnt bet on it however.
nice fish BTW.
