It’s hard to say anything from this video. I could not even understand which of the guys have the fin here on the surfing lineup, not the best drone work 
Did you test it with SUP on the flat water? Testing it with SUP would be a good start. Your closes competitor is Scubajet and Bixpy. They are more expensive and they give a weak propulsion of about 4-5Km/H for the SUP board.
When you have a prototypes ready, let me know, I would like to test it and share my opinion.