How long

[Otherone]

I don't even follow that rule anymore. with small tanks that rule could be somewhat true but once your tank gets big enough you can over stock to certain degree as long as filtration can keep up

Well said and I agree, the 20-30 gal. rule is more or less a guideline for those with limited experience raising juvi Piranha because when you get into adults the rules change. 20-25 gal won't cut it for Elongatus or Rhom's. On the flip side adult Pygo's aren't the most active openwater swimmers to begin with and can be shoehorned to an extent. Cannabalism generally stops by 5-6" so long as a sick adult fish isn't introduced to the shoal.

 

[impala]

A 180/220g with a 6'x2' foot print would be the way to go for these magnificent beasts to reach their maximum potential, imo.

 

[saints24]

I have a 125 with 9 rbp in it, I agree with what the others are saying, as long as the filtration is good and you maintain it you should be fine

 

[tellemuno]

i will more then likely go with the 180 aslong as the shoal does not thin out.(cannibalism} THANKS EVERYONE!