ok...im getting a 125 gal tank and right now i have a 55 gal tank and this is the tank mates...two pleco, one green terror, one irredecent shark, one leporanis (i think thats the spelling) and one convict. the kids brought home a tetra at the end of school two years ago and its still there....shock me and the greet terror had a baby....with who im not sure...probably the convict...lol. now my question is...they have all lived together two plus years and get along very well...shockingly...but if i get another bigger tank can i add more fish for there will be more space. they are all fairly good size...the pleco especially....but what could i put with them to make sure noone gets hurt....any advice will be appreciated.