DON'T GET IT...LOL. They are called tank busters for a reason...most ppl end up getting rid of them because of their size and it will limit what you can keep BIG TIME!!
I agree with everyone here... way too big, too fast for your tank. These guys are beasts and are always hungry... all stomach and mouth... they will even eat decor, lol.
Yeah your 120 is just a little bit too small, multiply the tank size by 10 and then you'll have an adequately sized tank. Maybe one day you'll be able to house one of these giants
if he eats really good he will out grow in a month maybe 2, but switching him from store to your tank may slow him down a wee bit. What size tank did he come from or at pet store?