What do mermaids use to wash their fins?

Tide.

More dad jokes you'll groan at

Did you hear about the man who cut off his left leg? He’s all right now.When a toddler reaches the "why?" stage, it's like opening a bottle of champagne— once it's uncorked, there's no going back.What did one ocean say to the other ocean? Nothing, they just waved.How did Benjamin Franklin feel when he discovered electricity? He was shocked!What's a crafty dancer's favorite hobby? Cutting a rugI ate a clock the other day. It was very time consuming.