I stick with northfin and NLS only. NLS has good 7-8% fiber, I feed some algaemax as well to get more veggie in. Good thing about NLS is all formulas use at least 6 type of algae and algaemax uses 9 types.
I don't think a flowerhorn needs high protein (more than 45 for Juvenile and more than 40 for adult) nutritionally. Most red dragons on low quality diet grow large humps, many African cichlids have awesome colors on low quality diet, even if they might not be in best potential health, Genetics for sure has to be there for looks.
What I was trying to say is my assumption is high temperature water works because it's a breeding favorable environment for fish and so should high protein. If I feed something like northfin carnivore formula temporarily for a week, it might have similar effect. This is speculation off course, since so many people swear by high protein.