I’ve read that reeling in a fish really slowly can help. Is that true?

In most cases, no. Some fish species, like salmon, pike or catfish, have a pneumatic duct that they can use to release, or “burp,” gases from their swim bladder. But many species in North Dakota, like walleye, perch and bass, do not have this duct. They regulate gases in their swim bladder through their bloodstream, which takes quite a long time. So when most anglers consider reeling a fish in slowly (say 3-5 minutes) to allow them to release gas from their swim bladder, it’s not nearly slow enough to be effective (more like 20-30 minutes).