I have a Bonsai even smaller than yours lol
This is a picture of how they look
This is taken from the FLOWERHORN INFO SHEETS
Final adult size is dependent on several factors such as body type, breed, and gender. Most Flowerhorn rarely push over 12 with around 10-11 being much more common. The average healthy growth for Flowerhorn is around 1 a month.
Short body Flowerhornwill vary greatly from one another. They could reach anywhere from 6-10 typically depending on the degree of short body. The Bonsai body type rarely seen at 8, they typically reach around 6-7 for males and 5-6 for females. Bonsai and short bodied Flowerhorn grow at a slightly slower rate than normal bodied Flowerhorn.