Under comfortable conditions Flowerhorns breed without any problems. There are some things that you should prepare beforehand though.
First, you would need a really large breeding tank as having them successfully breed in the common tank is unlikely. This in itself is a challenge given their size.
These species become fully mature at around 1.5-2 years. Some individuals might be ready to reproduce even earlier at only about 12 months of age.
The spawning process itself happens naturally and requires little to no stimulation. The females usually lay their eggs on a smooth substrate like rocks or ceramics. They lay up to 900 eggs which are then fertilized by the male.
If the male becomes especially aggressive, place a divider between him and the offspring.
The first juveniles start to hatch towards the end of the second day and two more days later they will begin to swim around. They can be fed brine shrimp or specific foods for juvenile fish that you can find in a store.
Parents will look after their young for about two months, after which you can place the young back into the common tank. They start developing their characteristic appearance at around 6 months and you will be able to tell the gender of the fish at the same time.