I don't know the Quadgrow system that well, but do use Autopots, which seem similar, in that the pots are sitting in a puddle all the time. They use them at Eden (where I first got the idea) and at Beechgrove, amongst other places. I've used mine for 5-10 years now, works well.
However, the manufacturer is quite keen to point out that the pots need to contain a free-draining mixture. When I bought mine, they recommended 70% soil or compost pus 30% perlite. This suggestion has since modified:-
https://autopot.co.uk/wp-content/upload ... s-Tips.pdfI use maybe 80/20 HM compost/vermiculite, with a layer of sterile bag compost on top to suppress weeds. The plants didn't get a week to establish but seem to be doing well. I don't put feed into the water, but use various organic feeds from a watering can. I once put organic tomato feed in the reservoir and 'subsequently found out it was based upon fish waste'
Mine have got tomatoes and cucumbers in them. 8 pots. 6 toms of 3 varieties and 2 cucumbers - one burpless, one crystal lemon. In the same greenhouse I've got another 8 terracotta pots sitting in growbag trays, another 6 toms and 2 burpless cues, plus 2 balconniere troughs, with serrano and cayenne chillies. Whilst I'm happy to flood these other trays when we're away, I try to keep them damp rather than wet if possible when we're around.
So dont despair, but maybe give some thought to the drainage.
HTH