If they have a fishy taste, it’s usually from preparation, not the fish itself. Catfish aren’t fishy tasting at all. Any red line should be cut out, and they should be filleted like other fish rather than skinned. And also like any fish, the quicker they go on ice, the better.
The above tips are right on, but there's something my mom used to do when we would bring fish home. She would always take our filets and soak them in milk for a few hours before cooking.
I have done this for years now with my own family and never have had any complaints about the flavor being too strong, plus it reminds me of mom!
If she thinks it is fishy tasting and was prepped right, soak the filets in buttermilk for a couple hours before frying. I don't even rinse the buttermilk off, straight into my recipe for my breading mix, then into the deep fryer.
__________________ 2013 Fishing Season
Largemouth Bass: 8
Smallmouth Bass: 0
White Bass: 0
Rock Bass: 0
Yellow Perch: 0
White Perch: 0
Channel Cats: 1