Sinking into the water, Joker blows some bubbles. Well, it's not as if he expected that to go through anyway. It's common enough for the two of them to stumble through these kind of things. Language barriers, what a pain... It only takes him a second to rise up a little more again.

Maybe something like... He touches his ear, the corner of his eye, and then his mouth before looking to Ginko expectantly.