Good man. I used to have a hydroponic tower too. And a whole bunch of hydroponic trays and water tanks with all the gadgets to check PH and CF. So much fun!
I've not started these lessons yet but for sure it's coming. They're only little :)
I've tried to explain how it all works but don't think it's going in. They do know where bananas come from though! Mostly coz of the monkeys round here trying to steal them all the time!
In time it'll all soak in. They are lucky to have a father who cares about their health and well-being from such an early age. I need to visit Bali, it sounds like a dream! I'll be over in Malysia and Singapore in a few months, maybe I can take a detour.