Fish aggression ratings

[duanes]

Cool! You live near Cenotes? Im trying to make a Cenote environment in my cichlid tank!

I do not live near Cenotes, but spent some time there in the Yucatan, snorkeling with the cichlids in a number of them, and obcserving how they lived
In most Cenotes the rocks were the size of compact cars
Here is some video from when was there.
This 1st Eden Cenote is mostly JDs and mollies
Eden2
In Aktun Ha I found Parachromis multifasciata, and introduced Tilapines
Aktun Ha
Azul mostly Mayaheros uropthalmus
Azul imovie edit
And below a small Cenote where JDs and uropthalmus were found
027 zps4b102ffd

 

[FINWIN]

Parrots go anywhere from 2-10...they're a box of chocolates. Wimps or nightmares, but some are in the middle. I have two nightmares, one in the middle, and one wimp. But they're all different and fun.

Even the wimp is aggressive to other parrots. The middle one is a tank boss, and the two nightmares would make a red devil proud.

The wimp is about a 6
The tank Boss an 8
The Bangers, 9 and 10 respectively

 

[FINWIN]

Yeah, lots of variables involved here. Another big one is age/size of fish. Plenty of cichlids and some other fish seem okay as youngsters, then become...either gradually or suddenly...homicidal once they hit some obscure growth milestone.

It's always entertaining to read some of those threads:

Aquarist #1: "Yeah, I bought a baby XYZ Psycho-Assassin Killer Cichlid and put him in my 10-gallon tank with some guppies. I don't know why these fish have such a bad rap; mine is best buddies with the guppies, and likes to school with them!"

Aquarist #2: "That's amazing! How long has he been in there with them?"

Aquarist #1: Checks the time on his phone...

LOL!!! This reminds me of Devil threads I've seen.

"My baby devil Is being picked on. He's really shy. I'm worried the GT will kill him."

(three months pass)

"HELP! I've found the floating head of my GT this morning. WHO COULD HAVE DONE IT?? It happened overnight!"

 

[The Masked Shadow]

You could be like a fish version of Schmidt’s Pain Scale. This looks fun!