I was about 15 feet over a moving stream so the water was no smooth clear surface and my Mavic 3 Pro flipped over and dove into the water for no apparent reason. I have read several times that 30 feet is a suggested safe height. I have also flow...
A safe altitude is when you can see the reflections of the water don't shimmer on the drones surface.
A minimum of 10 meters or 30 feet is my safe lowest flight level, but on a very sunny day with more reflection on the waters surface I will fly...
Staying a bit high over water is your friend. The movement of the water can sometimes confuse the sensors and you may get inaccurate readings for altitude from the controller.
If you want to fly really low just be prepared. You may have to save...