Mark-
Glad you want to do your part. A large reef tank is not the place to breed banggais, primarily becuz if they do bred you'll have no access to the fry, nor will you be able to control food. Thats said if you want a display tank-
here is my answer
2 banggais,
These fish are not haremic, they are not schooling and they are not like other apogons (cardinal fish). Once a pair forms expect the male to kill off all the others except his female.
Males and females are not monogamus, however due to intolerance for others in small tanks (under 1000 gal) only a few banggais/tank.
Maybe-just maybe you might get 3 banggais, but one will be hiding from the pair.
Yes 99.99% of all banggais are wild collected and yes w/in the next yr you will see these fish placed on CITES II restrictions, so there won't be anymore collections in a few years, so doing your part is important.
If you are interested in breeding these fish consider dividing up your 120 w/ physical dividers and place females and males in each section, otherwise-just 2 banggais.
FYI
The hello anyone comment- while funny is suggestive that you didn't look or search for potential answers. I'm not scolding you, I'm just saying alot of folks work or live overseas, and 4 hr may or maynot be enuf time
There are alot of good articles on banggais on the web, which are very clear
try these for starters
http://www.breedersregistry.org/Articles/v4_i4_marini/marini.htm
http://www.reefs.org/library/talklog/f_marini_020799.html
http://www.reefs.org/library/talklog/k_clarke_102499.html
http://www.reefs.org/library/article/f_marini.html
