How Many Fish
Good morning Shay...
If you have good filtration in your tank and do a large water change once a week, you can have 40 small, adult fish. By small, I mean no more than an inch to an inch and a half long, full grown. If you want larger fish, then your tank will safely support fewer fish.
I keep 55 G tanks of Fancy Guppies and have good filtration and do a 50 percent water change weekly. I keep around 150-200 individuals per tank.
"Fear not, my young apprentice. Just change the tank water."