Vulture still gonna push it in a 125 at 20" max. Search function on planet catfish will let you put in max desired size and you can narrow it down from there. I'd put in like a max size of nothing over 13-14".
If your 125 is at least 2' wide, Sorubim sp. Could work. The problem with this genus is just that you never know for sure which species you get.. Some will stay at a foot some might reach 20"