On January 03, 2004, about 1530 eastern standard time, a Maule, M-7-235B, N10430, registered to and operated by a private individual, as a Title 14 CFR Part 91, personal flight, pitched forward after landing on water at a private lake near Fort Lauderdale, Florida. Visual meteorological conditions prevailed at the time, and no flight plan was filed. The private-rated pilot reported no injuries and the airplane sustained substantial damage. The flight originated in Winterhaven, Florida, about 1400. According to the pilot he had performed four touch-and-go landings on several lakes at Winterhaven, Florida, and then continued to Butterfly Lake, Fort Lauderdale, Florida, for a full stop. He stated that the lake was "glassy" and the runway was 2,000 feet in length. The pilot lowered full flaps to make sure the airplane was going to stop in time. At touch down, the right float caught the water and the airplane pivoted forward, the right wing impacted the water and the airplane came to a stop inverted. He estimated the winds at 7 to 8 knots from the southeast, on the lake. The pilot stated that there was "no" mechanical failures prior to the accident. His safety recommendation on the NTSB Form 6120.1/2, was "...not using full flaps on glassy water."