When I asked if there was one best way to unclog a sink, master plumber Kassandra Hornik chuckled. That’s not how it works, she said. There are too many kinds of pipes and too many types of clogs.And even when the pipes and clogs are the same, Hornik and other industry pros I asked didn’t always agree on the best remedies.That said, there’s something of a loose consensus on a few strategies that tend to be safe, effective, affordable, and DIY-friendly. Other popular quick fixes, including a few seemingly harmless hacks, are much more controversial among members of the trade.Here’s what you need to know when the sink drains won’t flow. And, fair warning, you still might need to call a plumber in the end.