Keep in mind I haven't done my research, but the idea might be to measure ph/tds with an arduino and dispense from a nutrient/ph resovior accordingly. Also have an extra water pump just for circulating the water around the bottom. Thoughts? I'm curious to know how its done in the marketplace

MIL: Maybe something like an aerogarden or personalized cutting/ charcuterie board.

FIL: A unique whiskey decanter and glasses

Or for both, look into unique games on Amazon - there are a ton and would work for both.