another question for the fish guys

I honestly don’t have the fish picked out specifically yet. I have 2 bala sharks that are about 4 or 5 inches and one smaller one. Everything I’ve read about them says they should be in a longer tank about 6 foot once mature. I e-mailed the person asking for measurements on the tank and stand and haven’t heard back yet. With the number of fish I have in the tank now I vaccum siphon it every other week and the tank says fairly clean inbetween changes. Current tank is a 60 gallon. I want a 125 so that I can put the current tropical fish I have into that and have room to add to the tropical community collection and use my 60 for African cichlids or something else.