What is this? You burst a ballon with water? I think for sure I would set my shutter speed to your synch speed (i assume 1/250 or 1/200, not sure). Then it's all depend on your flash unit and the power supply. I would certainly set it to manual and start with 1/8 power. I assume with 1/8 power you will get about 8 burst shot. If 8 frames is not enough, then make the power lower. Adjust the ISO to get the desired exposure.
This is just what I think I would do if I attempt the shot. I have never done one before so take it with a grain of salt!