New Super Mario Bros. U: Meringue Clouds-5 -- A Quick Dip in the Sky

This is a vertical level featuring floating water bubbles. Mario can swim in these to reach new places. The first Star Coin is circling three giant Piranha Plants. The easiest way to get it is to kill the Piranha Plants with fireballs, then jump to get it. Go up and you'll reach the midpoint. If you need a power-up, there's a Red Coin Ring nearby. Swim up between two Piranha Plants and go right of a water bubble with a Fuzzy in it. There's a hidden area with a pipe cannon that will take you to the second Star Coin. The third Star Coin is in a water bubble with two Fuzzies circling it. At the top is the pipe to the flagpole. This opens the path to Meringue Clouds-6.