Ummm.
You were doing well right up the the part about taking off in 25-30 feet.
About the only electric that is going to get off the water in that distance is a parkflier or something with a bit more power than a $50 motor will provide.
A glider with floats might take off in that distance, but is still questionable.
Why the limit on the take off distance? If your pond is that small you better be darn good to land on it!