i want a mixed aro tank, but how?

[dmopar74]

i already got a silver around 16" who seems pretty agro compared to other silvers i have owned but not a "killer", and i would like to add some other species like black and leichardti. are there any tricks to adding other aro's, or just throw em in and hope for the best? ive heard about three or more should help. im just trying to do some sort of research before i throw 400-500$ worth of aro's in the tank.
other fish that would be in tank are:
spotted gar(which the silver pays no attn. too even thoughit sorta looks the same as an aro. i mean long and thin, you get my point.)
2 ck's
pleco
3 pbass
and some sevs and blood parrots if room at the time

tank is 7'x30"x24"high(not currently but soon, BEFORE they need a tank that size).

 

[headbanger_jib]

you might try introducing an aro with a divider for sometime
my lfs had a RTG which was 10"
and then he got a new RTG which was 6"
he put in a divider in the 180g half for each and after a few months when the small got to 10" he removed the divider and they don't fight(whenever i have seen them) anyways there were no other fish in the tank

or there might be a chance that my lfs just got lucky

 

[Bderick67]

all you really can do is introduce the new aros and hope for the best. Just make sure you have an alternate tank, so you can move one of the aros if needed. My smaller silver fought with my black which was a bit smaller, but got along fine when he was placed with another silver.