I just happen to have an old swimming pool lying around... oh, wait... no, that was at the last mansion I lived at ;)

Fantastic post! The closest I got to the old swimming pool solution was filling my granddaughter's paddling pool with potting compost and growing carrots this year. It worked well, shielded the seedlings from carrot fly etc, so if it survives the winter, I'll use it again.
Hydroponics would be perfect for me, I have a pond with koi, so I hoped to recycle their water through the roots. It didn't happen this year, maybe next...