Stardew Valley has plenty of fish in the sea. And lakes. And ponds. And rivers. Look, the point is there’s a ton for you to catch. One such fish (that is also necessary for a Community Center bundle) is the Sandfish.
The Sandfish is a bit rare, though, so you won’t have that easy of a time catching one. The easiest way to get a hold of one is by fixing the bus that will allow you head over to Calico Desert. Once there, fishing at the pond will offer you the chance to nab a Sandfish.
There you have it, a steady supply of Sandfish is at the palm of your hand! These sell for 75 coins, 93 coins if Silver Star, and 112 coins if Gold Star. You might also get lucky and be able to buy one from the Travelling Cart, but this is your best bet.
If you need more help with Stardew Valley, check out our wiki!