The size of baitfish you'll want to catch will depend on several factors. The species of fish you are after is an important consideration for this, but some species, like freshwater stripers, can prefer a different size bait on different days. Cast net mesh sizes range from about 3/8 of an inch all the way up to an inch or more. Obviously, if you want to catch small baitfish, you'll want to get a cast net with smaller mesh. Large bait can be caught in either. Consequently, nets with small mesh are the most versatile, since they allow you to catch baitfish in a wider variety of sizes.