HI, BC!
Sounds like you've discovered a very exciting ride. A word of caution tho...
Scuba divers will confirm this: Shooting down 30 ft and back in "a blink of an eye" is a great recipe for a ruptured eardrum. The inrush of cold water creates instant, strongly disorienting vertigo (dizzyness and total lack of orientation to vertical). Being 30ft down, dizzy, disoriented, clinging to a hydrofoil while being dragged through the briny by a motorboat sounds a little too real. (Unknowingly roll to inverted, attempt to surface in a panic, crush head on bottom.)
Other airbound cavities in the human body also react poorly to rapid descent/ascent. Good news: don't worry about the bends; 30 ft is a "no-decompression depth, even if you were down long enough, which is pretty tough w/out canned air.
Suggest you take it slow on the ups and downs.