Underwater drone from GoPro and two bottles :)

I'm a poor diver. I can't hold my breath for long, so I'm not very good at filming underwater, especially if I'm without a wetsuit and a weight belt. Right now, the water around me is heated to 29°C, and the air is over 30°C. If I put on neoprene, I’d cook alive! I came up with an idea to lower the camera to depth while staying on the surface. My first attempts were unsuccessful; I couldn't stabilize the camera in the direction of movement. I solved this problem by placing the camera's standard handle inside a bottle filled with gravel and attaching two control lines to the surface. Here's what I got: watch until the end :)