They grow rather quickly. I bought mine with my Trimac, Zonatus, Synspilum, and Argentea. They were bought all at 3-3.5"
He grew to 6 by the time the others reached 4.5" over 4 months.
Then he killed my Argentea and Synspilum, He was even hammering on
my male Trimac. Needless to say he was removed. Replaced Syns with a 5" Bifa and have another 5" Argentea on way. Peace has settled since he was removed.
They become quite aggressive