Your fish list looks good, but as someone above posted you need good filtration...I also have a 120 gallon and i'm running an eheim 2217, eheim pro II 2026, and xp2....now with the exception of the xp2 I got the eheim canister filters used and for a decent price...try searching for craiglist,kijiji,or any online buy and sell site in your area....I used to have a those HOB filter and they get load and annoying after a while and won't be as good as canisters......
