Could take something like a 793 GPH (3000 LPH) 35W air pump using a 12V 100W solar panel with a 12 Volt DC to AC Power Inverter. This will be heavy enough so we can forget a charge controller and batteries. * this is 3000 litres per hour of air injected into water. I can envisage this setup weighing about 15-20kg, but it shouldn’t be a problem with a larger hull
I really am not happy with fountain now, as wind will interfere, and the cost + weight + energy to get a 2-3m fountain is off-putting. I think to stick with an air pump to inject air into
Air pumps will have to be off-the-shelf components rather than made myself!