fish fight

Hi all. This is my first post. I have an 850L hardscape tank. I am going for a community tank and have about 20 rummy nose tetra, 20 cardinal tetras, 5 white fin tetra, 6 plecos, 3 bristlenose catfish , and 10 cherries (5m/5F). I got 4 fancy guppies today, and the female cherries have killed...

I have had this Uaru for 5 years got him as an adult he was a rescue and I never wanted to keep him this long. He ended up killing my severum stressed him out to death I should have gotten rid of him then. This fish once was nice and ok with tank mates now he is a jerk even to the silver...