Would three of these fish work in a 55?

[cciesielski]

it sucks everywhere around where i live dont have green severums ne more only turquoise ones and my grandparents had a green one that they said i could have but it got eaten and it was huge (like10") no joke their pacu ate it

 

[WolfFisho1]

blue dempseys die pretty easily but once they get large they look sweet good luck tryin to keep one of them a liv for more than a year!

 

[GooDyboy420]

I love terrors, i would go with a green terror and severums, just introduce hte gt last

 

[Skoomakilla]

it sucks everywhere around where i live dont have green severums ne more only turquoise ones and my grandparents had a green one that they said i could have but it got eaten and it was huge (like10") no joke their pacu ate it

how big was this pacu??