AH....the wonderful temperament of cichlids.
The biggest problem with FH's is they grow so dang fast "an inch per week" and then become dominant.
As soon as mine grew larger then my JD the relentless attack was on but not for long as i removed all my juveniles from my 55 and transfered them over to my 135 and giving the 55 to the FH all to himself or may return him to the LFS.
All is well again,JD is healed up and getting cocky.